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Sample records for lethal endotoxic shock

  1. Clarithromycin expands CD11b+Gr-1+ cells via the STAT3/Bv8 axis to ameliorate lethal endotoxic shock and post-influenza bacterial pneumonia

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    Fujii, Hideki; Yagi, Kazuma; Suzuki, Shoji; Hegab, Ahmed E.; Tasaka, Sadatomo; Nakamoto, Nobuhiro; Iwata, Satoshi; Honda, Kenya; Kanai, Takanori; Hasegawa, Naoki; Betsuyaku, Tomoko

    2018-01-01

    Macrolides are used to treat various inflammatory diseases owing to their immunomodulatory properties; however, little is known about their precise mechanism of action. In this study, we investigated the functional significance of the expansion of myeloid-derived suppressor cell (MDSC)-like CD11b+Gr-1+ cells in response to the macrolide antibiotic clarithromycin (CAM) in mouse models of shock and post-influenza pneumococcal pneumonia as well as in humans. Intraperitoneal administration of CAM markedly expanded splenic and lung CD11b+Gr-1+ cell populations in naïve mice. Notably, CAM pretreatment enhanced survival in a mouse model of lipopolysaccharide (LPS)-induced shock. In addition, adoptive transfer of CAM-treated CD11b+Gr-1+ cells protected mice against LPS-induced lethality via increased IL-10 expression. CAM also improved survival in post-influenza, CAM-resistant pneumococcal pneumonia, with improved lung pathology as well as decreased interferon (IFN)-γ and increased IL-10 levels. Adoptive transfer of CAM-treated CD11b+Gr-1+ cells protected mice from post-influenza pneumococcal pneumonia. Further analysis revealed that the CAM-induced CD11b+Gr-1+ cell expansion was dependent on STAT3-mediated Bv8 production and may be facilitated by the presence of gut commensal microbiota. Lastly, an analysis of peripheral blood obtained from healthy volunteers following oral CAM administration showed a trend toward the expansion of human MDSC-like cells (Lineage−HLA-DR−CD11b+CD33+) with increased arginase 1 mRNA expression. Thus, CAM promoted the expansion of a unique population of immunosuppressive CD11b+Gr-1+ cells essential for the immunomodulatory properties of macrolides. PMID:29621339

  2. The Antimalarial Chloroquine Suppresses LPS-Induced NLRP3 Inflammasome Activation and Confers Protection against Murine Endotoxic Shock

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    Xiaoli Chen

    2017-01-01

    Full Text Available Activation of the NLRP3 inflammasome, which catalyzes maturation of proinflammatory cytokines like IL-1β and IL-18, is implicated and essentially involved in many kinds of inflammatory disorders. Chloroquine (CQ is a traditional antimalarial drug and also possesses an anti-inflammatory property. In this study, we investigated whether CQ suppresses NLRP3 inflammasome activation and thereby confers protection against murine endotoxic shock. CQ attenuated NF-κB and MAPK activation and prohibited expression of IL-1β, IL-18, and Nlrp3 in LPS treated murine bone marrow-derived macrophages (BMDMs, demonstrating its inhibitory effect on the priming signal of NLRP3 activation. Then, CQ was shown to inhibit caspase-1 activation and ASC specks formation in BMDMs, which indicates that CQ also suppresses inflammasome assembly, the second signal for NLRP3 inflammasome activation. In a murine endotoxic shock model, CQ effectively improved survival and markedly reduced IL-1β and IL-18 production in serum, peritoneal fluid, and lung tissues. Moreover, CQ reduced protein levels of NLRP3 and caspases-1 p10 in lung homogenates of mice with endotoxic shock, which may possibly explain its anti-inflammatory activity and life protection efficacy in vivo. Overall, our results demonstrate a new role of CQ that facilitates negative regulation on NLRP3 inflammasome, which thereby confers protection against lethal endotoxic shock.

  3. Overexpression of human SOD1 improves survival of mice susceptible to endotoxic shock

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    Charchaflieh J

    2012-07-01

    Full Text Available Jean Charchaflieh,1,2 Georges I Labaze,1 Pulsar Li,1 Holly Van Remmen,3 Haekyung Lee,1 Helen Stutz,1 Arlan Richardson,3 Asher Emanuel,1 Ming Zhang1,41Department of Anesthesiology, State University of New York (SUNY Downstate Medical Center, New York, NY, USA; 2Department of Anesthesiology, Yale University School of Medicine, New Haven, CT, USA; 3Barshop Center for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA; 4Department of Cell Biology, State University of New York (SUNY Downstate Medical Center, New York, NY, USABackground: Protective effects of the antioxidant enzyme Cu-Zn superoxide dismutase (SOD1 against endotoxic shock have not been demonstrated in animal models. We used a murine model to investigate whether overexpression of SOD1 protects against endotoxic shock, and whether the genetic background of SOD1 affects its effective protective effects and susceptibility to endotoxic shock.Methods: Transgenic (tg mice overexpressing human SOD1 and control mice were divided into four groups based on their genetic background: (1 tg mice with mixed genetic background (tg-JAX; (2 wild-type (WT littermates of tg-JAX strain (WT-JAX; (3 tg mice with C57BL/6J background (tg-TX; (4 WT littermates of tg-TX strain (WT-TX. Activity of SOD1 in the intestine, heart, and liver of tg and control mice was confirmed using a polyacrylamide activity gel. Endotoxic shock was induced by intraperitoneal injection of lipopolysaccharide. Survival rates over 120 hours (mean, 95% confidence interval were analyzed using Kaplan–Meier survival curves.Results: Human SOD1 enzymatic activities were significantly higher in the intestine, heart, and liver of both tg strains (tg-JAX and tg-TX compared with their WT littermates (WT-JAX and WT-TX, respectively. Interestingly, the endogenous SOD1 activities in tg-JAX mice were decreased compared with their WT littermates (WT-JAX, but such aberrant changes were not

  4. Trehalose: a biophysics approach to modulate the inflammatory response during endotoxic shock.

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    Minutoli, Letteria; Altavilla, Domenica; Bitto, Alessandra; Polito, Francesca; Bellocco, Ersilia; Laganà, Giuseppina; Fiumara, Tiziana; Magazù, Salvatore; Migliardo, Federica; Venuti, Francesco Saverio; Squadrito, Francesco

    2008-07-28

    We evaluated the effects of trehalose against endotoxic shock, a condition in which the loss of bio-membrane integrity plays a pivotal role. In addition we performed a biophysics experiment by quasi elastic neutron scattering (QENS) study, to investigate whether the membrane stability effect of trehalose might be correlated with its high capability to switch-off the water diffusive dynamics and, hence, the kinetic mechanisms of interaction. Endotoxic shock was induced in male rats by a single injection of Salmonella enteritidis lipopolysaccharide (LPS; 20 mg/kg/i.p.). Thirty minutes before and 2 h after LPS injection, the animals were randomized to receive vehicle (1 ml/kg/i.p. 0.9%NaCl), sucrose (1 g/kg/i.p.) or trehalose (1 g/kg/i.p.). Mean arterial blood pressure, nuclear factor-kappaB (NF-kappaB) binding activity, Ikappa-Balpha and toll-like receptor-4 (TLR-4) activation were evaluated in both liver and lung. Plasmatic tumor necrosis factor-alpha (TNF-alpha), interleukin-1 (IL-1), interleukin-6 (IL-6) and malondialdehyde (MDA) were also investigated. We studied liver injury by means of blood alanine aminotransferase activity (ALT); inducible nitric oxide synthase (iNOS) expression, myeloperoxidase (MPO) activity and tissue edema evaluation. Lung injury was investigated by means of tissue monocyte chemoattractant protein-1 (MCP-1) levels, MPO activity, iNOS expression and edema formation. Trehalose reduced hypotension, NF-kappaB binding activity, IkappaBalpha protein loss and TLR-4 activation. In addition trehalose reduced TNF-alpha, IL-1, IL-6 and MDA levels. Trehalose also blunted liver and lung injury. QENS measurements showed also that trehalose possesses a high "switching off" capability. Sucrose did not modify endotoxic shock-induced sequelae. Trehalose blocked the inflammatory cascade triggered by endotoxin shock, stabilizing the bio-membranes and switching off the water diffusive dynamics.

  5. Interferon Regulatory Factor 6 Has a Protective Role in the Host Response to Endotoxic Shock.

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    Sophie Joly

    Full Text Available Interferon Regulatory Factor (IRF 6, a member of the IRF family, is essential for epidermal and orofacial embryonic development. Irf6 is strongly expressed in keratinocytes, in which it regulates epidermal proliferation, differentiation, and migration. A recent role for Irf6 in Toll-like receptor 2-dependent chemokine gene expression was also reported in an epithelial cell line. However, a function for Irf6 in innate immune cells was not previously reported. In the present study, we investigated the expression and function of Irf6 in bone marrow-derived neutrophils and macrophages. We show here, using a conditional knockout of Irf6 in lysosymeM expressing cells, that Irf6 is required for resistance to LPS-induced endotoxic shock. In addition, Irf6-deficient bone marrow-derived neutrophils exhibited increased chemotactic index and velocity compared with wild-type cells in vitro. TLR4-specific KC and IL6 secretions were upregulated in Irf6-deficient bone marrow-derived macrophages in vitro. These cells also exhibited an increased level of phosphorylated IkBa. Collectively, our findings suggest a role for Irf6 in the resistance to endotoxic shock due to NFk-B-mediated alteration of cytokine production.

  6. COMPARATIVE EFFICACY OF HYPERTONIC SALINE AND NORMAL SALINE SOLUTIONS IN EXPERIMENTALLY INDUCED ENDOTOXIC SHOCK IN DOGS

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    M. A. ZAFAR, G. MUHAMMAD, M. H. HUSSAIN, T. AHMAD, A. YOUSAF AND I. SARFARAZ

    2009-07-01

    Full Text Available This study was contemplated to determine the comparative beneficial effects of hypertonic saline solution and sterile saline solution in induced endotoxic shock in dogs. For this purpose, 12 healthy Mongrel dogs were randomly divided into two equal groups (A and B. All the animals were induced endotoxaemia by slow intravenous administration of Escherichia coli endotoxins 0111:B4. Group A was treated with normal saline solution @ 90 ml/kg BW, while group B was given hypertonic saline solution @ 4 ml/kg BW, followed by normal saline solution @ 10 ml/kg BW. Different parameters were observed for evaluation of these fluids including clinical and haematological parameters, serum electrolytes, mean arterial pressure, and blood gases at different time intervals up to 24 hours post treatments. After infusion of respective fluids, all parameters returned to baseline values in both the groups but group B showed better results than group A except bicarbonates, which better recovered in group A. Thus, it was concluded that a small-volume of hypertonic saline solution could be effectively used in reversing the endotoxaemia. Moreover, it provides a rapid and inexpensive resuscitation from endotoxic shock.

  7. Effects of Ibuprofen on the physiology and outcome of rabbit endotoxic shock

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    Canbaz Mukaddes

    2002-10-01

    Full Text Available Abstract Background Despite major developments in the management of septic shock, the mortality rate had progressively increased. Ibuprofen has been shown to have beneficial physiological effects when used as a treatment. However, there are conflicting results with respect to survival. This study aims to investigate the effect of ibuprofen on vital functions, various physiological parameters and survival during endotoxic shock in rabbits. Methods Twenty-eight New Zealand rabbits were randomly separated into four groups. The first group received only saline, the second was given 2 mg/kg intravenous endotoxin at t0, the third received 30 mg/kg ibuprofen 30 minutes after endotoxin administration, whilst the fourth group received ibuprofen 30 minutes before the endotoxin. Respiratory and heart rate, mean arterial blood pressure and rectal temperature were recorded. Complete blood counts were performed and thromboxane B2 was measured every 30 minutes for the first two hours, and then hourly over the course of the experiment. Urine samples were collected at the same time points for the measurement of prostaglandin E2. Results Ibuprofen was found to improve respiratory rate, heart rate, and arterial pressure. However, it did not improve the negative effects of endotoxin on body temperature, haematocrit values, white blood cell count, and thrombocyte number. Thromboxane B2 levels in group IV were significantly lower than in the other groups, and the increase started at a later timepoint. In ibuprofen-treated animals, Prostaglandin E2 levels stayed low for at least 90 minutes, but started to rise thereafter. While the average survival in Group II animals was 192.9 ± 46.9 minutes, those of groups III and IV were 339.1 ± 33.5 minutes (p Conclusions Ibuprofen appears to increase survival in endotoxic shock-induced animals. Therefore, it may be helpful for the prophylaxis and treatment of patients with, or who are likely to develop, septic shock.

  8. Effects and mechanisms of cavidine protecting mice against LPS-induced endotoxic shock

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    Li, Weifeng, E-mail: liwf@mail.xjtu.edu.cn; Zhang, Hailin; Niu, Xiaofeng, E-mail: niuxf@mail.xjtu.edu.cn; Wang, Xiumei; Wang, Yu; He, Zehong; Yao, Huan

    2016-08-15

    LPS sensitized mice are usually considered as an experimental model of endotoxin shock. The present study aims to evaluate effects of cavidine on LPS-induced endotoxin shock. Mice were intraperitoneally administrated with cavidine (1, 3 and 10 mg/kg) or DEX (5 mg/kg) at 1 and 12 h before injecting LPS (30 mg/kg) intraperitoneally. Blood samples, liver, lung and kidney tissues were harvested after LPS injection. The study demonstrated that pretreatment with cavidine reduced the mortality of mice during 72 h after endotoxin injection. In addition, cavidine administration significantly attenuated histological pathophysiology features of LPS-induced injury in lung, liver and kidney. Furthermore, cavidine administration inhibited endotoxin-induced production of pro-inflammatory cytokines including TNF-α, IL-6 and HMGB1. Moreover, cavidine pretreatment attenuated the phosphorylation of mitogen-activated protein kinase primed by LPS. In summary, cavidine protects mice against LPS-induced endotoxic shock via inhibiting early pro-inflammatory cytokine TNF-α, IL-6 and late-phase cytokine HMGB1, and the modulation of HMGB1 may be related with MAPK signal pathway. - Highlights: • Cavidine significantly reduced mortality in mice during 72 h after LPS injection. • Cavidine attenuated histopathological changes in lung, liver and kidney. • Cavidine decreased the level of early inflammatory cytokine TNF-α, IL-6 in LPS- stimulated mice. • Cavidine inhibited late inflammatory cytokine HMGB1 through MAPK pathway.

  9. The novel role of platelet-activating factor in protecting mice against lipopolysaccharide-induced endotoxic shock.

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    Young-Il Jeong

    Full Text Available BACKGROUND: Platelet-activating factor (PAF has been long believed to be associated with many pathophysiological processes during septic shock. Here we present novel activities for PAF in protecting mice against LPS-mediated endotoxic shock. PRINCIPAL FINDINGS: In vivo PAF treatment immediately after LPS challenge markedly improved the survival rate against mortality from endotoxic shock. Administration of PAF prominently attenuated LPS-induced organ injury, including profound hypotension, excessive polymorphonuclear neutrophil infiltration, and severe multiple organ failure. In addition, PAF treatment protects against LPS-induced lymphocytes apoptosis. These protective effects of PAF was correlated with significantly decreases in the production of the inflammatory mediators such as TNF-alpha, IL-1beta, IL-12, and IFN-gamma, while increasing production of the anti-inflammatory cytokine IL-10 in vivo and in vitro. CONCLUSIONS: Taken together, these results suggest that PAF may protect mice against endotoxic shock via a complex mechanism involving modulation of inflammatory and anti-inflammatory mediators.

  10. Effect of leukotriene receptor antagonists on vascular permeability during endotoxic shock

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    Cook, J.A.; Li, E.J.; Spicer, K.M.; Wise, W.C.; Halushka, P.V.

    1990-01-01

    Evidence has accumulated that sulfidopeptide leukotrienes are significant pathogenic mediators of certain hematologic and hemodynamic sequelae of endotoxic shock. In the present study, the effects of a selective LTD4/E4 receptor antagonist, LY171883 (LY), or a selective LTD4 receptor antagonist, SKF-104353 (SKF), were assessed on splanchnic and pulmonary localization of 99mTechnetium-labeled human serum albumin (99mTc-HSA) in acute endotoxic shock in the rat. Dynamic gamma camera imaging of heart (H), midabdominal (GI), and lung regions of interest generated time activity curves for baseline and at 5-35 min after Salmonella enteritidis endotoxin (10 mg/kg, i.v.). Slopes of GI/H and lung/H activity (permeability index, GI/H or lung/H X 10(-3)/min) provided indices of intestinal and lung localization. Rats received LY (30 mg/kg, i.v.), LY vehicle (LY Veh), SKF (10 mg/kg), or SKF vehicle (SK Veh) 10 min prior to endotoxin or endotoxin vehicle. In rats receiving the LY Veh and endotoxin (n = 8) or SKF Veh and endotoxin (n = 12), the splanchnic permeability indices to 99mTc-HSA were increased 11.2-fold and 5.1-fold, respectively (P less than 0.05) compared to vehicle control groups not given endotoxin (n = 5). Pulmonary permeability index for 99mTc-HSA was increased (P less than 0.05) to a lesser extent (3.2-fold) by endotoxin compared to vehicle controls. Pretreatment with SKF reduced the mesenteric permeability index to control levels (P less than 0.05) during the 5-35 min time interval post-endotoxin. LY reduced the mesenteric permeability index by 70%. Pulmonary relative permeability to 99mTc-HSA was not affected by LY pretreatment. Both splanchnic and lung relative permeability to the isotope was transient; at 135-225 min post-endotoxin, splanchnic localization of 99mTc-HSA (n = 4) was not significantly different from vehicle controls in these vascular beds

  11. Administration of colistin sulfate in endotoxic model at slow and sustained fashion may reverse shock without causing nephrotoxicity in its optimal concentration.

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    Haque, Anwarul; Ishii, Yoshikazu; Akasaka, Yoshikiyo; Matsumoto, Tetsuya; Tateda, Kazuhiro

    2017-12-01

    Despite of proven LPS neutralizing activity, intravenous polymyxin use was waned due to experience of associated nephrotoxicity. But, increasing resistance to all available antibiotics has necessitated their resurgence and the prodrug of colistin sulfate (CS), known as colistin-methanesulfonate (CMS), is increasingly used as the only therapeutic option in many infections. Currently available CMS employ very different dose definitions and thus because of complex pharmacokinetics/pharmacodynamics information and short half-life, this drug use remains confusing. We aimed to expose CS in endotoxic shock models by micro-osmotic pump and evaluated its effectiveness. We used micro-osmotic pumps to deliver either sterile saline or CS at different dosages ranging from 0.25mg/day to 7mg/day for consecutive 3days in LPS (8mg/kg body weight) induced endotoxic mice and observed their outcome twice daily for a week to determine the survival rate. Serum pro-inflammatory cytokine levels and apoptosis in renal tissues in these models were evaluated. We showed endotoxic shock was reversed and all mice survived with a CS administration at a dosage of 2mg/day for 3 days, in comparison to survival rate with saline administration (p≤0.0001) in endotoxic models. CS infusion in shock models using micro-osmotic pump ameliorated rising of serum TNF-α, IL-12p70 and IL-6 levels. Nephrotoxicity was evident only with a higher dosage, but not with a lower dosage which was optimum to control endotoxic shock in models. These results highlighted that an optimal dosage of CS effectively improved outcome in endotoxic shock models without causing nephrotoxicity when administered at a slow and sustained manner. And a higher CS dosage administration was nephrotoxic and fatal. Thus this study bought an opportunity to consider future investigations with CS administration in murine Gram-negative bacterial infections in a novel way. Copyright © 2017 International Society for Chemotherapy of Infection

  12. Plumbagin, a vitamin K3 analogue, abrogates lipopolysaccharide-induced oxidative stress, inflammation and endotoxic shock via NF-κB suppression.

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    Checker, Rahul; Patwardhan, Raghavendra S; Sharma, Deepak; Menon, Jisha; Thoh, Maikho; Sandur, Santosh K; Sainis, Krishna B; Poduval, T B

    2014-04-01

    Plumbagin has been reported to modulate cellular redox status and suppress NF-κB. In the present study, we investigated the effect of plumbagin on lipopolysaccharide (LPS)-induced endotoxic shock, oxidative stress and inflammatory parameters in vitro and in vivo. Plumbagin inhibited LPS-induced nitric oxide, TNF-α, IL-6 and prostaglandin-E2 production in a concentration-dependent manner in RAW 264.7 cells without inducing any cell death. Plumbagin modulated cellular redox status in RAW cells. Plumbagin treatment significantly reduced MAPkinase and NF-κB activation in macrophages. Plumbagin prevented mice from endotoxic shock-associated mortality and decreased serum levels of pro-inflammatory markers. Plumbagin administration ameliorated LPS-induced oxidative stress in peritoneal macrophages and splenocytes. Plumbagin also attenuated endotoxic shock-associated changes in liver and lung histopathology and decreased the activation of ERK and NF-κB in liver. These findings demonstrate the efficacy of plumbagin in preventing LPS-induced endotoxemia and also provide mechanistic insights into the anti-inflammatory effects of plumbagin.

  13. Dynamics and distribution of /sup 3/H-dopamine in serum and tissues of heart, brain and adrenal glands of rats with endotoxic shock

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    Rainov, A; Boschkov, B; Nikolov, N [Meditsinska Akademiya, Sofia (Bulgaria)

    1980-04-01

    The dynamics and the distribution of /sup 3/H-dopamine in the serum and tissues of the heart, hypothalamus, cerebral cortex and adrenal glands were studied in 60 Wistar rats. The rats received intravenously 7.4 MBq /sup 3/H-dopamine/kg body weight 10 minutes before they were killed. The experimental animals were subjected to endotoxic shock by injecting them with 2 mg endotoxin of E. coli O 111:B/sub 4//kg body weight, and killed after 5, 10, 15, 20 and 30 min, respectively. Maximum increase of the tritium activity in the organs investigated was observed 20 min after the shock.

  14. CD44-deficiency attenuates the immunologic responses to LPS and delays the onset of endotoxic shock-induced renal inflammation and dysfunction.

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    Elena Rampanelli

    Full Text Available Acute kidney injury (AKI is a common complication during systemic inflammatory response syndrome (SIRS, a potentially deadly clinical condition characterized by whole-body inflammatory state and organ dysfunction. CD44 is a ubiquitously expressed cell-surface transmembrane receptor with multiple functions in inflammatory processes, including sterile renal inflammation. The present study aimed to assess the role of CD44 in endotoxic shock-induced kidney inflammation and dysfunction by using CD44 KO and WT mice exposed intraperitoneally to LPS for 2, 4, and 24 hours . Upon LPS administration, CD44 expression in WT kidneys was augmented at all time-points. At 2 and 4 hours, CD44 KO animals showed a preserved renal function in comparison to WT mice. In absence of CD44, the pro-inflammatory cytokine levels in plasma and kidneys were lower, while renal expression of the anti-inflammatory cytokine IL-10 was higher. The cytokine levels were associated with decreased leukocyte influx and endothelial activation in CD44 KO kidneys. Furthermore, in vitro assays demonstrated a role of CD44 in enhancing macrophage cytokine responses to LPS and leukocyte migration. In conclusion, our study demonstrates that lack of CD44 impairs the early pro-inflammatory cytokine response to LPS, diminishes leukocyte migration/chemotaxis and endothelial activation, hence, delays endotoxic shock-induced AKI.

  15. Zein-Based Nanoparticles Improve the Oral Bioavailability of Resveratrol and Its Anti-inflammatory Effects in a Mouse Model of Endotoxic Shock.

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    Penalva, Rebeca; Esparza, Irene; Larraneta, Eneko; González-Navarro, Carlos J; Gamazo, Carlos; Irache, Juan M

    2015-06-17

    Resveratrol offers pleiotropic health benefits including a reported ability to inhibit lipopolysaccharide (LPS)-induced cytokine production. The aim of this work was to prepare, characterize, and evaluate a resveratrol nanoparticulate formulation based on zein. For this purpose, the oral bioavailability of the encapsulated polyphenol as well as its anti-inflammatory effects in a mouse model of endotoxic shock was studied. The resveratrol-loaded nanoparticles displayed a mean size of 307 ± 3 nm, with a negative zeta potential (-51.1 ± 1.55 mV), and a polyphenol loading of 80.2 ± 3.26 μg/mg. In vitro, the release of resveratrol from the nanoparticles was found to be pH independent and adjusted well to the Peppas-Sahlin kinetic model, suggesting a mechanism based on the combination of diffusion and erosion of the nanoparticle matrix. Pharmacokinetic studies demonstrated that zein-based nanoparticles provided high and prolonged plasma levels of the polyphenol for at least 48 h. The oral bioavailability of resveratrol when administered in these nanoparticles increased up to 50% (19.2-fold higher than for the control solution of the polyphenol). Furthermore, nanoparticles administered daily for 7 days at 15 mg/kg were able to diminish the endotoxic symptoms induced in mice by the intraperitoneal administration of LPS (i.e., hypothermia, piloerection, and stillness). In addition, serum tumor necrosis factor-alpha (TNF-α) levels were slightly lower (approximately 15%) than those observed in the control.

  16. Role of Nrf2/ARE pathway in protective effect of electroacupuncture against endotoxic shock-induced acute lung injury in rabbits.

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    Jian-bo Yu

    Full Text Available NF-E2 related factor 2 (Nrf2 is a major transcription factor and acts as a key regulator of antioxidant genes to exogenous stimulations. The aim of current study was to determine whether Nrf2/ARE pathway is involved in the protective effect of electroacupuncture on the injured lung in a rabbit model of endotoxic shock. A dose of lipopolysaccharide (LPS 5 mg/kg was administered intravenously to replicate the model of acute lung injury induced by endotoxic shock. Electroacupuncture pretreatment was handled bilaterally at Zusanli and Feishu acupoints for five consecutive days while sham electroacupuncture punctured at non-acupoints. Fourty anesthetized New England male rabbits were randomized into normal control group (group C, LPS group (group L, electroacupuncture + LPS group (group EL and sham electroacupuncture + LPS (group SEL. At 6 h after LPS administration, the animals were sacrificed and the blood samples were collected for biochemical measurements. The lungs were removed for calculation of wet-to-dry weight ratios (W/D, histopathologic examination, determination of heme oxygenase (HO-1 protein and mRNA, Nrf2 total and nucleoprotein, as well as Nrf2 mRNA expression, and evaluation of the intracellular distribution of Nrf2 nucleoprotein. LPS caused extensive morphologic lung damage, which was lessened by electroacupuncture treatment. Besides, lung W/D ratios were significantly decreased, the level of malondialdehyde was inhibited, plasma levels of TNF-α and interleukin-6 were decreased, while the activities of superoxide dismutase, glutathione peroxidase and catalase were enhanced in the electroacupucnture treated animals. In addition, electroacupuncture stimulation distinctly increased the expressions of HO-1 and Nrf2 protein including Nrf2 total protein and nucleoprotein as well as mRNA in lung tissue, while these effects were blunted in the sham electroacupuncture group. We concluded that electroacupuncture treatment at ST36 and BL13

  17. Role of Nrf2/ARE pathway in protective effect of electroacupuncture against endotoxic shock-induced acute lung injury in rabbits.

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    Yu, Jian-bo; Shi, Jia; Gong, Li-rong; Dong, Shu-an; Xu, Yan; Zhang, Yuan; Cao, Xin-shun; Wu, Li-li

    2014-01-01

    NF-E2 related factor 2 (Nrf2) is a major transcription factor and acts as a key regulator of antioxidant genes to exogenous stimulations. The aim of current study was to determine whether Nrf2/ARE pathway is involved in the protective effect of electroacupuncture on the injured lung in a rabbit model of endotoxic shock. A dose of lipopolysaccharide (LPS) 5 mg/kg was administered intravenously to replicate the model of acute lung injury induced by endotoxic shock. Electroacupuncture pretreatment was handled bilaterally at Zusanli and Feishu acupoints for five consecutive days while sham electroacupuncture punctured at non-acupoints. Fourty anesthetized New England male rabbits were randomized into normal control group (group C), LPS group (group L), electroacupuncture + LPS group (group EL) and sham electroacupuncture + LPS (group SEL). At 6 h after LPS administration, the animals were sacrificed and the blood samples were collected for biochemical measurements. The lungs were removed for calculation of wet-to-dry weight ratios (W/D), histopathologic examination, determination of heme oxygenase (HO)-1 protein and mRNA, Nrf2 total and nucleoprotein, as well as Nrf2 mRNA expression, and evaluation of the intracellular distribution of Nrf2 nucleoprotein. LPS caused extensive morphologic lung damage, which was lessened by electroacupuncture treatment. Besides, lung W/D ratios were significantly decreased, the level of malondialdehyde was inhibited, plasma levels of TNF-α and interleukin-6 were decreased, while the activities of superoxide dismutase, glutathione peroxidase and catalase were enhanced in the electroacupucnture treated animals. In addition, electroacupuncture stimulation distinctly increased the expressions of HO-1 and Nrf2 protein including Nrf2 total protein and nucleoprotein as well as mRNA in lung tissue, while these effects were blunted in the sham electroacupuncture group. We concluded that electroacupuncture treatment at ST36 and BL13 effectively

  18. Awara (Astrocaryum vulgare M.) pulp oil: chemical characterization, and anti-inflammatory properties in a mice model of endotoxic shock and a rat model of pulmonary inflammation.

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    Bony, Emilie; Boudard, Frédéric; Brat, Pierre; Dussossoy, Emilie; Portet, Karine; Poucheret, Patrick; Giaimis, Jean; Michel, Alain

    2012-01-01

    Awara (Astrocaryum vulgare M.) is a palm fruit mainly used in nutrition. We analysed the pulp oil for fatty acid, tocopherol, carotenoid, and phytosterol and we evaluated whether this oil may attenuate inflammation in vivo. In an endotoxic shock model, awara pulp oil treatment decreased pro-inflammatory cytokines and increased anti-inflammatory cytokines. In a pulmonary inflammation model, awara pulp oil treatment reduced eosinophil and lymphocyte numbers recovered into the broncho-alveolar lavages. These results suggest that awara pulp oil administration can efficiently counteract an acute and chronic inflammatory response in vivo that is probably mediated by fatty acids and minor compounds. Copyright © 2011 Elsevier B.V. All rights reserved.

  19. Chemical composition and anti-inflammatory properties of the unsaponifiable fraction from awara (Astrocaryum vulgare M.) pulp oil in activated J774 macrophages and in a mice model of endotoxic shock.

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    Bony, Emilie; Boudard, Frédéric; Dussossoy, Emilie; Portet, Karine; Brat, Pierre; Giaimis, Jean; Michel, Alain

    2012-12-01

    Awara (Astrocaryum vulgare M.) pulp oil has been shown to possess anti-inflammatory properties in vivo, and contains an unsaponifiable matter rich in bioactive compounds. This study focused on the ethanolic unsaponifiable fraction (EUF) of awara pulp oil. Its chemical composition has been characterized: carotenoid, phytosterol, and tocopherol contents represent 125.7, 152.6, and 6.8 μg/mg of EUF, respectively. We further evaluated this fraction for anti-inflammatory properties in J774 macrophages activated by lipopolysaccharide (LPS) plus interferon (IFN) γ to understand the biological effects of awara pulp oil. EUF strongly decreased nitric oxide (NO), prostaglandin E(2), tumour necrosis factor (TNF) α, and interleukin (IL) -6 and -10 production in activated J774 cells. Moreover, it inhibited expression of inducible NO synthase and cyclooxygenases-2 in vitro. The anti-inflammatory properties of EUF were also confirmed in vivo by modulation of TNFα, IL-6 and IL-10 serum concentration in an endotoxic shock model. Pre-treatment with awara oil fraction offers promise as a protective means to lower the production of excessive amounts of pro-inflammatory molecules.

  20. Survival of Primates in Lethal Septic Shock Following Delayed Treatment with Steroid.

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    1981-02-26

    TECHNICAL REPORT NO. 142 SURVIVAL OF PRIMATES IN LETHAL SEPTIC SHOCK FOLLOWING DELAYED TREAMENT WIn STEROID L. B. Hinshaw, L. T. Archer, B. K. Belier ...2. Schumer W: Steroids in the treatment of clinical septic shock. Ann Surg 184:333-341, 1976. 3. Hinshaw LB, Belier PK, Archer LT, Flournoy DJ, White...not preventable by antibiotic alone. Infect Immun ZS:538-5)7, 1979. 6. Hinshaw LB, Archer LT, Belier -Todd BK, Coalson .JJ, Flournoy DL, Passey R

  1. Insoluble glycogen, a metabolizable internal adsorbent, decreases the lethality of endotoxin shock in rats

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    S. Sipka

    1997-01-01

    Full Text Available Insoluble glycogen is an enzymatically modified form of naturally occurring soluble glycogen with a great adsorbing capacity. It can be metabolized by phagocytes to glucose. In this study we used insoluble glycogen intravenously in the experimental endotoxin shock of rats. Wistar male rats were sensitized to endotoxin by Pb acetate. The survival of rats were compared in groups of animals endotoxin shock treated and non-treated with insoluble glycogen. Furthermore, we have determined in vitro the binding capacity of insoluble glycogen for endotoxin, tumour necrosis factor alpha, interleukin-1 and secretable phospholipase A2. Use of 10 mg/kg dose of insoluble glycogen could completely prevent the lethality of shock induced by LD50 quantity of endotoxin in rats. All animals treated survived. Insoluble glycogen is a form of ‘metabolizable internal adsorbents’. It can potentially be used for treatment of septic shock.

  2. Protective effect of ciliary neurotrophic factor (CNTF) in a model of endotoxic shock: action mechanisms and role of CNTF receptor alpha.

    Science.gov (United States)

    Demitri, M T; Benigni, F; Meazza, C; Zinetti, M; Fratelli, M; Villa, P; Acheson, A; Panayotatos, N; Ghezzi, P

    1998-01-01

    Ciliary neurotrophic factor (CNTF) inhibits the production of tumor necrosis factor (TNF) in lipopolysaccharide (LPS)-treated mice and protects against LPS lethality when coadministered with its soluble receptor (sCNTFR alpha). Both of these activities are abolished in adrenalectomized (ADX) mice. LPS-induced pulmonary polymorphonuclear neutrophil (PMN) infiltration and nitric oxide (NO) production were also inhibited by CNTF + sCNTFR alpha but not by CNTF alone. sCNTFR alpha did not alter the clearance or tissue distribution of CNTF. Furthermore, CNTF variants coadministered with sCNTFR alpha protected against LPS toxicity in a manner related to their affinity for the beta components of CNTFR. Thus, inhibition of TNF production and protection against LPS lethality by CNTF/sCNTFR alpha require an intact hypothalamus-pituitary-adrenal axis (HPAA) and may be mediated by endogenous glucocorticoids. This protective effect is, at least in part, due to the inhibition of PMN infiltration and NO production, and appears to be mediated by cells displaying only beta-receptor subtypes.

  3. The effects of aspirin, flurbiprofen, and NO-donating acetylsalicylic acid (NCX 4016) on mice models of endotoxic and septic shock.

    Science.gov (United States)

    Ulu, Nadir; Iskit, Alper Bektaş; Sökmensüer, Cenk; Güç, Mustafa Oğuz

    2015-01-01

    Nitric oxide-donating nonsteroidal antiinflammatory drugs (NO-NSAIDs) are a promising new class of antiinflammatory agents, which are obtained by adding NO-donating moieties to the existing conventional NSAID molecules. The aim of this study was to investigate the effects of aspirin, flurbiprofen, and NO-donating acetylsalicylic acid (NCX 4016) on cecal ligation and puncture (CLP) and endotoxin-induced septic shock (LPS) models in mice. Overall survival and spleen and liver weights were monitored in LPS and CLP models. Histopathological examinations of liver and spleen were performed at the end of the experimental protocols. NCX 4016 was able to reverse the increased spleen weight in CLP-operated animals, whereas aspirin or flurbiprofen did not. Similar to the results of the CLP model, none of the drugs modified the survival rates in the LPS model. Flurbiprofen in particular produced significant histopathological damage in spleens and livers, which was less significant with aspirin. NCX 4016 did not cause any liver damage. NCX 4016 has the potential to be used in septic states, while special attention has to be paid to the effects of aspirin and flurbiprofen on the liver and spleen.

  4. Basal and insulin-stimulated skeletal muscle sugar transport in endotoxic and bacteremic rats

    International Nuclear Information System (INIS)

    Westfall, M.V.; Sayeed, M.M.

    1988-01-01

    Membrane glucose transport with and without insulin was studied in soleus muscle from 5-h endotoxic rats (40 mg/kg Salmonella enteritidis lipopolysaccharide), and in soleus and epitrochlearis muscles from 12-h bacteremic (Escherichia coli, 4 X 10(10) CFU/kg) rats. Glucose transport was measured in muscles by evaluating the fractional efflux of 14 C-labeled 3-O-methylglucose ( 14 C-3-MG) after loading muscles with 14 C-3-MG. Basal 3-MG transport was elevated in soleus muscles from endotoxic as well as in soleus and epitrochlearis muscles from bacteremic rats compared with time-matched controls. Low insulin concentrations stimulated 14 C-3-MG transport more in bacteremic and endotoxic rat muscles than in controls. However, sugar transport in the presence of high insulin dose was attenuated in soleus and epitrochlearis muscles from bacteremic rats and soleus muscles from endotoxic rats compared with controls. Analysis of the dose-response relationship with ALLFIT revealed that the maximal transport response to insulin was significantly decreased in both models of septic shock. Sensitivity to insulin (EC50) was increased in endotoxic rat muscles, and a somewhat similar tendency was observed in bacteremic rat soleus muscles. Neural and humoral influences and/or changes in cellular metabolic energy may contribute to the increase in basal transport. Shifts in insulin-mediated transport may be due to alterations in insulin-receptor-effector coupling and/or the number of available glucose transporters

  5. Prokaryotic Selectivity, Anti-endotoxic Activity and Protease Stability of Diastereomeric and Enantiomeric Analogs of Human Antimicrobial Peptide LL-37

    International Nuclear Information System (INIS)

    Nan, Yong Hai; Lee, Bongju; Shin, Song Yub

    2012-01-01

    LL-37 is the only antimicrobial peptide (AMP) of the human cathelicidin family. In addition to potent antimicrobial activity, LL-37 is known to have the potential to inhibit lipolysaccharide (LPS)-induced endotoxic effects. To provide the stability to proteolytic digestion and increase prokaryotic selectivity and/or anti-endotoxic activity of two Lys/Trp-substituted 19-meric anti-microbial peptides (a4-W1 and a4-W2) designed from IG-19 (residues 13-31 of LL-37), we synthesized the diastereomeric peptides (a4-W1-D and a4-W2-D) with D-amino acid substitution at positions 3, 7, 10, 13 and 17 of a4-W1 and a4-W2, respectively and the enantiomeric peptides (a4-W1-E and a4-W2-E) composed D-amino acids. The diastereomeric peptides exhibited the best prokaryotic selectivity and effective protease stability, but no or less anti-endotoxic activity. In contrast, the enantiomeric peptides had not only prokaryotic selectivity and anti-endotoxic activity but also protease stability. Our results suggest that the hydrophobicity and α-helicity of the peptide is important for anti-endotoxic activity. In particular, the enantiomeric peptides showed potent anti-endotoxic and LPS-neutralizing activities comparable to that of LL-37. Taken together, both a4-W1-E and a4-W2-E holds promise as a template for the development of peptide antibiotics for the treatment of endotoxic shock and sepsis

  6. Prokaryotic Selectivity, Anti-endotoxic Activity and Protease Stability of Diastereomeric and Enantiomeric Analogs of Human Antimicrobial Peptide LL-37

    Energy Technology Data Exchange (ETDEWEB)

    Nan, Yong Hai; Lee, Bongju; Shin, Song Yub [Chosun Univ., Gwangju (Korea, Republic of)

    2012-09-15

    LL-37 is the only antimicrobial peptide (AMP) of the human cathelicidin family. In addition to potent antimicrobial activity, LL-37 is known to have the potential to inhibit lipolysaccharide (LPS)-induced endotoxic effects. To provide the stability to proteolytic digestion and increase prokaryotic selectivity and/or anti-endotoxic activity of two Lys/Trp-substituted 19-meric anti-microbial peptides (a4-W1 and a4-W2) designed from IG-19 (residues 13-31 of LL-37), we synthesized the diastereomeric peptides (a4-W1-D and a4-W2-D) with D-amino acid substitution at positions 3, 7, 10, 13 and 17 of a4-W1 and a4-W2, respectively and the enantiomeric peptides (a4-W1-E and a4-W2-E) composed D-amino acids. The diastereomeric peptides exhibited the best prokaryotic selectivity and effective protease stability, but no or less anti-endotoxic activity. In contrast, the enantiomeric peptides had not only prokaryotic selectivity and anti-endotoxic activity but also protease stability. Our results suggest that the hydrophobicity and α-helicity of the peptide is important for anti-endotoxic activity. In particular, the enantiomeric peptides showed potent anti-endotoxic and LPS-neutralizing activities comparable to that of LL-37. Taken together, both a4-W1-E and a4-W2-E holds promise as a template for the development of peptide antibiotics for the treatment of endotoxic shock and sepsis.

  7. Electric shocks are ineffective in treatment of lethal effects of rattlesnake envenomation in mice.

    Science.gov (United States)

    Johnson, E K; Kardong, K V; Mackessy, S P

    1987-01-01

    Electrical shocks, even crudely delivered from 'stun guns' and gasoline engine spark plugs, have been reported to be effective in the treatment of snake bite. We thus applied similar electric shocks to mice artificially injected with reconstituted rattlesnake venom at various LD50 multiples. Those envenomated mice treated with electric shock survived no better than the controls. We thus found no evidence that electric shocks crudely administered had any life saving effect in mice.

  8. Non-lethal heat shock increased Hsp70 and immune protein transcripts but not Vibrio tolerance in the white-leg shrimp.

    Directory of Open Access Journals (Sweden)

    Nguyen Hong Loc

    Full Text Available Non-lethal heat shock boosts bacterial and viral disease tolerance in shrimp, possibly due to increases in endogenous heat shock protein 70 (Hsp70 and/or immune proteins. To further understand the mechanisms protecting shrimp against infection, Hsp70 and the mRNAs encoding the immune-related proteins prophenoloxidase (proPO, peroxinectin, penaeidin, crustin and hemocyanin were studied in post-larvae of the white-leg shrimp Litopenaeus vannamei, following a non-lethal heat shock. As indicated by RT-qPCR, a 30 min abrupt heat shock increased Hsp70 mRNA in comparison to non-heated animals. Immunoprobing of western blots and quantification by ELISA revealed that Hsp70 production after heat shock was correlated with enhanced Hsp70 mRNA. proPO and hemocyanin mRNA levels were augmented, whereas peroxinectin and crustin mRNA levels were unchanged following non-lethal heat shock. Penaeidin mRNA was decreased by all heat shock treatments. Thirty min abrupt heat shock failed to improve survival of post-larvae in a standardized challenge test with Vibrio harveyi, indicating that under the conditions of this study, L. vannamei tolerance to Vibrio infection was influenced neither by Hsp70 accumulation nor the changes in the immune-related proteins, observations dissimilar to other shrimp species examined.

  9. Non-Lethal Heat Shock Increased Hsp70 and Immune Protein Transcripts but Not Vibrio Tolerance in the White-Leg Shrimp

    Science.gov (United States)

    Loc, Nguyen Hong; MacRae, Thomas H.; Musa, Najiah; Bin Abdullah, Muhd Danish Daniel; Abdul Wahid, Mohd. Effendy; Sung, Yeong Yik

    2013-01-01

    Non-lethal heat shock boosts bacterial and viral disease tolerance in shrimp, possibly due to increases in endogenous heat shock protein 70 (Hsp70) and/or immune proteins. To further understand the mechanisms protecting shrimp against infection, Hsp70 and the mRNAs encoding the immune-related proteins prophenoloxidase (proPO), peroxinectin, penaeidin, crustin and hemocyanin were studied in post-larvae of the white-leg shrimp Litopenaeus vannamei, following a non-lethal heat shock. As indicated by RT-qPCR, a 30 min abrupt heat shock increased Hsp70 mRNA in comparison to non-heated animals. Immunoprobing of western blots and quantification by ELISA revealed that Hsp70 production after heat shock was correlated with enhanced Hsp70 mRNA. proPO and hemocyanin mRNA levels were augmented, whereas peroxinectin and crustin mRNA levels were unchanged following non-lethal heat shock. Penaeidin mRNA was decreased by all heat shock treatments. Thirty min abrupt heat shock failed to improve survival of post-larvae in a standardized challenge test with Vibrio harveyi, indicating that under the conditions of this study, L. vannamei tolerance to Vibrio infection was influenced neither by Hsp70 accumulation nor the changes in the immune-related proteins, observations dissimilar to other shrimp species examined. PMID:24039886

  10. Oxygen radicals in experimental shock: effects of spin-trapping nitrones in ameliorating shock pathophysiology (see comments)

    Energy Technology Data Exchange (ETDEWEB)

    Novelli, G.P. (Institute of Anesthesiology and Intensive Care, University of Florence, Careggi Hospital, (Italy))

    1992-04-01

    Circulatory shock is accepted as a consequence of an acute oxygen radical overgeneration. Spin-trapping nitrones inactivate free radicals by forming relatively stable adducts. Three spin-trapping nitrones (N-tert-phenyl-butyl-nitrone; alpha-4-pyridyl-oxide-N-tert-butyl-nitrone; 5-5,dimethyl,1,pyrroline-N-oxide) were tested regarding their role in the pathophysiology and evolution of circulatory shock in rats. A prospective, randomized, controlled trial of spin-trapping nitrones in rats experiencing three different models of circulatory shock was designed. In the first group, endotoxic, traumatic, and mesenteric artery occlusion shock (all 100% lethal in control experiments) was prevented by the ip administration of N-tert-phenyl-butyl-nitrone (150 mg/kg); alpha-4-pyridyl-oxide-N-tert-butyl-nitrone (100 mg/kg); or 5-5,dimethyl,1,pyrroline-N-oxide (100 mg/kg). However, the evolution of shock was unaffected by the same compounds when all three nitrones had been previously inactivated by exposure to light and air. In the second group, microcirculatory derangements that were provoked by endotoxin and were observed in the mesocecum of rats were completely prevented by pretreatment with either peritoneal administration of each of the three nitrones or by their topical application to the microscopic field. While the rats survived after systemic treatment, those rats receiving topical nitrones died from endotoxic shock. In the third group, cell-membrane stiffness (a sign of peroxidative damage) was measured by spin-probes and electron-spin resonance in mitochondrial and microsomal membranes. Cell membranes obtained from shocked rats were more rigid than those membranes of controls. However, the membranes obtained from rats that were submitted to trauma or endotoxin after pretreatment with N-tert-phenyl-butyl-nitrone had normal stiffness.

  11. DMPD: Cytokines, PGE2 and endotoxic fever: a re-assessment. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 15967158 Cytokines, PGE2 and endotoxic fever: a re-assessment. Blatteis CM, Li S, L... (.svg) (.html) (.csml) Show Cytokines, PGE2 and endotoxic fever: a re-assessment. PubmedID 15967158 Title C...ytokines, PGE2 and endotoxic fever: a re-assessment. Authors Blatteis CM, Li S, L

  12. Binding of superantigen toxins into the CD28 homodimer interface is essential for induction of cytokine genes that mediate lethal shock.

    Directory of Open Access Journals (Sweden)

    Gila Arad

    2011-09-01

    Full Text Available Bacterial superantigens, a diverse family of toxins, induce an inflammatory cytokine storm that can lead to lethal shock. CD28 is a homodimer expressed on T cells that functions as the principal costimulatory ligand in the immune response through an interaction with its B7 coligands, yet we show here that to elicit inflammatory cytokine gene expression and toxicity, superantigens must bind directly into the dimer interface of CD28. Preventing access of the superantigen to CD28 suffices to block its lethality. Mice were protected from lethal superantigen challenge by short peptide mimetics of the CD28 dimer interface and by peptides selected to compete with the superantigen for its binding site in CD28. Superantigens use a conserved β-strand/hinge/α-helix domain of hitherto unknown function to engage CD28. Mutation of this superantigen domain abolished inflammatory cytokine gene induction and lethality. Structural analysis showed that when a superantigen binds to the T cell receptor on the T cell and major histocompatibility class II molecule on the antigen-presenting cell, CD28 can be accommodated readily as third superantigen receptor in the quaternary complex, with the CD28 dimer interface oriented towards the β-strand/hinge/α-helix domain in the superantigen. Our findings identify the CD28 homodimer interface as a critical receptor target for superantigens. The novel role of CD28 as receptor for a class of microbial pathogens, the superantigen toxins, broadens the scope of pathogen recognition mechanisms.

  13. Ion transport in circulatory and/or septic shock

    International Nuclear Information System (INIS)

    Sayeed, M.M.

    1987-01-01

    This review surveys investigations of membrane ion transport in animals in hemorrhagic, endotoxic, or bacteremic shock. The focus of the review is on ion transport studies in the skeletal muscle and liver. Skeletal muscle Na + -K + transport alterations have been shown during the induction of shock via hemorrhage, endotoxin, or live Gram-negative bacteria in the rodent, canine, and primate species. These alterations include impairment of active cellular K + accumulation, increased permeability to 24 Na + and Cl - , and membrane depolarization. The ion transport alterations in the skeletal muscle are compatible with movement of extracellular fluid into the intracellular compartment. Such fluid movements can potentially lead to decreases in circulating plasma volume and thus to circulatory deficits in shock. Studies in the liver of rats subjected to hemorrhagic or endotoxic shock indicated the failure of electrogenic Na + pump. Although the hepatic cellular membrane permeability to Na + relative to permeability to K + appeared unaltered in hemorrhagic shock, endotoxic shock caused an increase in permeability to Na + . Hepatic cellular 45 Ca + regulation also appeared to be adversely affected during endotoxic shock. Alterations in hepatic Na + -K + transport and Ca + regulation could contribute to impairment in hepatic glucose production during shock. Although mechanisms of altered membrane ion transport during shock states remain unknown, such changes could occur prior to any substantial loss of cellular metabolic energy

  14. Cytotoxicity and Hsp 70 induction in Hep G2 cells in response to zearalenone and cytoprotection by sub-lethal heat shock

    International Nuclear Information System (INIS)

    Hassen, Wafa; Golli, Emna El; Baudrimont, Isabelle; Mobio, A. Theophile; Ladjimi, M. Moncef; Creppy, E. Edmond; Bacha, Hassen

    2005-01-01

    Zearalenone (ZEN) is a mycotoxin with several adverse effects in laboratory and domestic animals. The mechanism of ZEN toxicity that involves mainly binding to oestrogen receptors and inhibition of macromolecules synthesis is not fully understood. Using human hepatocytes Hep G2 cells as a model, the aim of this work was (i) to investigate the ability of ZEN to induce heat shock proteins Hsp 70 and (ii) to find out the mechanisms of ZEN cytotoxicity by examining cell proliferation and protein synthesis. Our study demonstrated that ZEN induces Hsp 70 expression in a time and dose-dependant manner; this induction occurs at non-cytotoxic concentrations, it could be therefore considered as a biomarker of toxicity. A cytoprotective effect of Hsp 70 was elicited when Hep G2 cells were exposed to Sub-Lethal heat shock prior to ZEN treatment and evidenced by a reduced ZEN cytolethality. This cytoprotection suggests that Hsp 70 may constitute an important cellular defence mechanism. Finally, our data show that ZEN is cytotoxic in Hep G2 cells by inhibiting cell proliferation and total protein synthesis and pointed out oxidative damage as possible pathway involved in ZEN toxicity; however, other investigations are needed to further confirm Zen induced oxidative stress

  15. Importance of lipopolysaccharide aggregate disruption for the anti-endotoxic effects of heparin cofactor II peptides.

    Science.gov (United States)

    Singh, Shalini; Papareddy, Praveen; Kalle, Martina; Schmidtchen, Artur; Malmsten, Martin

    2013-11-01

    Lipid membrane and lipopolysaccharide (LPS) interactions were investigated for a series of amphiphilic and cationic peptides derived from human heparin cofactor II (HCII), using dual polarization interferometry, ellipsometry, circular dichroism (CD), cryoTEM, and z-potential measurements. Antimicrobial effects of these peptides were compared to their ability to disorder bacterial lipid membranes, while their capacity to block endotoxic effects of LPS was correlated to the binding of these peptides to LPS and its lipid A moiety, and to charge, secondary structure, and morphology of peptide/LPS complexes. While the peptide KYE28 (KYEITTIHNLFRKLTHRLFRRNFGYTLR) displayed potent antimicrobial and anti-endotoxic effects, its truncated variants KYE21 (KYEITTIHNLFRKLTHRLFRR) and NLF20 (NLFRKLTHRLFRRNFGYTLR) provide some clues on structure-activity relations, since KYE21 retains both the antimicrobial and anti-endotoxic effects of KYE28 (although both attenuated), while NLF20 retains the antimicrobial but only a fraction of the anti-endotoxic effect, hence locating the anti-endotoxic effects of KYE28 to its N-terminus. The antimicrobial effect, on the other hand, is primarily located at the C-terminus of KYE28. While displaying quite different endotoxic effects, these peptides bind to a similar extent to both LPS and lipid A, and also induce comparable LPS scavenging on model eukaryotic membranes. In contrast, fragmentation and densification of LPS aggregates, in turn dependent on the secondary structure in the peptide/LPS aggregates, correlate to the anti-endotoxic effect of these peptides, thus identifying peptide-induced packing transitions in LPS aggregates as key for anti-endotoxic functionality. This aspect therefore needs to be taken into account in the development of novel anti-endotoxic peptide therapeutics. Copyright © 2013. Published by Elsevier B.V.

  16. Thalidomide protects mice against LPS-induced shock

    Directory of Open Access Journals (Sweden)

    Moreira A.L.

    1997-01-01

    Full Text Available Thalidomide has been shown to selectively inhibit TNF-a production in vitro by lipopolysaccharide (LPS-stimulated monocytes. TNF-a has been shown to play a pivotal role in the pathophysiology of endotoxic shock. Using a mouse model of LPS-induced shock, we investigated the effects of thalidomide on the production of TNF-a and other cytokines and on animal survival. After injection of 100-350 µg LPS into mice, cytokines including TNF-a, IL-6, IL-10, IL-1ß, GM-CSF and IFN-g were measured in the serum. Administration of 200 mg/kg thalidomide to mice before LPS challenge modified the profile of LPS-induced cytokine secretion. Serum TNF-a levels were reduced by 93%, in a dose-dependent manner, and TNF-a mRNA expression in the spleens of mice was reduced by 70%. Serum IL-6 levels were also inhibited by 50%. Thalidomide induced a two-fold increase in serum IL-10 levels. Thalidomide treatment did not interfere with the production of GM-CSF, IL-1ß or IFN-g. The LD50 of LPS in this model was increased by thalidomide pre-treatment from 150 µg to 300 µg in 72 h. Thus, at otherwise lethal doses of LPS, thalidomide treatment was found to protect animals from death

  17. Lethal Epistaxis.

    Science.gov (United States)

    Byard, Roger W

    2016-09-01

    Epistaxis or nosebleed refers to bleeding from the nostrils, nasal cavity, or nasopharynx. Occasional cases may present with torrential lethal hemorrhage. Three cases are reported to demonstrate particular features: Case 1: A 51-year-old woman with lethal epistaxis with no obvious bleeding source; Case 2: A 77-year-old man with treated nasopharyngeal carcinoma who died from epistaxis arising from a markedly neovascularized tumor bed; Case 3: A 2-year-old boy with hemophilia B who died from epistaxis with airway obstruction in addition to gastrointestinal bleeding. Epistaxis may be associated with trauma, tumors, vascular malformations, bleeding diatheses, infections, pregnancy, endometriosis, and a variety of different drugs. Careful dissection of the nasal cavity is required to locate the site of hemorrhage and to identify any predisposing conditions. This may be guided by postmortem computerized tomographic angiography (PCTA). Despite careful dissection, however, a source of bleeding may never be identified. © 2016 American Academy of Forensic Sciences.

  18. Construction of Escherichia coli Mutant with Decreased Endotoxic Activity by Modifying Lipid A Structure

    Directory of Open Access Journals (Sweden)

    Qiong Liu

    2015-05-01

    Full Text Available Escherichia coli BL21 (DE3 and its derivatives are widely used for the production of recombinant proteins, but these purified proteins are always contaminated with lipopolysaccharide (LPS. LPS is recognized by the toll-like receptor 4 and myeloid differentiation factor 2 complex of mammalian immune cells and leads to release of pro-inflammatory cytokines. It is a vital step to remove LPS from the proteins before use for therapeutic purpose. In this study, we constructed BL21 (DE3 ∆msbB28 ∆pagP38 mutant, which produces a penta-acylated LPS with reduced endotoxicity. The plasmids harboring pagL and/or lpxE were then introduced into this mutant to further modify the LPS. The new strain (S004 carrying plasmid pQK004 (pagL and lpxE produced mono-phosphoryated tetra-acylated lipid A, which induces markedly less production of tumor necrosis factor-α in the RAW264.7 and IL-12 in the THP1, but still retains ability to produce recombinant proteins. This study provides a strategy to decrease endotoxic activity of recombinant proteins purified from E. coli BL21 backgrounds and a feasible approach to modify lipid A structure for alternative purposes such as mono-phosphoryl lipid A (MPL as vaccine adjuvants.

  19. Electroshock weapons can be lethal!

    Science.gov (United States)

    Lundquist, Marjorie

    2008-03-01

    Electroshock weapons (EWs)-stun guns, tasers, riot shields-are electroconductive devices designed to safely incapacitate healthy men neuromuscularly, so they are called nonlethal or less-lethal. EW firms seeking large nonmilitary markets targeted law enforcement and corrections personnel, who began using EWs in prisons/jails and on public patrol in 1980 in the USA. This shifted the EW-shocked population from healthy soldiers to a heterogeneous mix of both sexes, ages 6-92, in a wide variety of health conditions! An EW operates by disrupting normal physiological processes, producing transient effects in healthy people. But if a person's health is sufficiently compromised, the margin of safety can be lost, resulting in death or permanent health problems. 325 people have died after EW shock since 1980. Did the EW cause these deaths? Evidence indicates that EWs do play a causal role in most such deaths. EWs can be lethal for people in diabetic shock^1 (hypoglycemia), which may be why Robert Dziekanski-a Polish immigrant to Canada-died so quickly after he was tasered at Vancouver Airport: not having eaten for over 10 hours, he likely was severely hypoglycemic. The EW death rate in North America is 30 times higher than need be, because EW users have not been properly trained to use EWs on a heterogeneous population safely! ^1J. Clinical Engineering 30(3):111(2005).

  20. Lethal mechanisms in gastric volvulus.

    Science.gov (United States)

    Omond, Kimberley J; Byard, Roger W

    2017-01-01

    A 55-year-old wheelchair-bound woman with severe cerebral palsy was found at autopsy to have marked distention of the stomach due to a volvulus. The stomach was viable, and filled with air and fluid and had pushed the left dome of the diaphragm upwards causing marked compression of the left lung with a mediastinal shift to the right (including the heart). There was no evidence of gastric perforation, ischaemic necrosis or peritonitis. Removal of the organ block revealed marked kyphoscoliosis. Histology confirmed the viability of the stomach and biochemistry showed no dehydration. Death in cases of acute gastric volvulus usually occurs because of compromise of the gastric blood supply resulting in ischaemic necrosis with distention from swallowed air and fluid resulting in perforation with lethal peritonitis. Hypovolaemic shock may also occur. However, the current case demonstrates an alternative lethal mechanism, that of respiratory compromise due to marked thoracic organ compression.

  1. Anti-endotoxic and antibacterial effects of a dermal substitute coated with host defense peptides.

    Science.gov (United States)

    Kasetty, Gopinath; Kalle, Martina; Mörgelin, Matthias; Brune, Jan C; Schmidtchen, Artur

    2015-01-01

    Biomaterials used during surgery and wound treatment are of increasing importance in modern medical care. In the present study we set out to evaluate the addition of thrombin-derived host defense peptides to human acellular dermis (hAD, i.e. epiflex(®)). Antimicrobial activity of the functionalized hAD was demonstrated using radial diffusion and viable count assays against Gram-negative Escherichia coli, Pseudomonas aeruginosa and Gram-positive Staphylococcus aureus bacteria. Electron microscopy analyses showed that peptide-mediated bacterial killing led to reduced hAD degradation. Furthermore, peptide-functionalized hAD displayed endotoxin-binding activity in vitro, as evidenced by inhibition of NF-κB activation in human monocytic cells (THP-1 cells) and a reduction of pro-inflammatory cytokine production in whole blood in response to lipopolysaccharide stimulation. The dermal substitute retained its anti-endotoxic activity after washing, compatible with results showing that the hAD bound a significant amount of peptide. Furthermore, bacteria-induced contact activation was inhibited by peptide addition to the hAD. E. coli infected hAD, alone, or after treatment with the antiseptic substance polyhexamethylenebiguanide (PHMB), yielded NF-κB activation in THP-1 cells. The activation was abrogated by peptide addition. Thus, thrombin-derived HDPs should be of interest in the further development of new biomaterials with combined antimicrobial and anti-endotoxic functions for use in surgery and wound treatment. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  2. Histopathological effects of lethal and sub-lethal concentrations of ...

    African Journals Online (AJOL)

    The histopathological effects of lethal and sub-lethal concentrations of glyphosate on African catfish Clarias gariepinus were investigated. C. gariepinus juveniles were assessed in a static renewal bioassay for 96 hours (acute toxicity) and 28 days (chronic toxicity) using varying concentrations (0.0 mg/l 20.0 mg/l, 30.0 mg/l, ...

  3. Suicide Lethality: A Concept Analysis.

    Science.gov (United States)

    DeBastiani, Summer; De Santis, Joseph P

    2018-02-01

    Suicide is a significant health problem internationally. Those who complete suicide may have different behaviors and risk factors than those who attempt a non-fatal suicide. The purpose of this article is to analyze the concept of suicide lethality and propose a clear definition of the concept through the identification of antecedents, attributes, and consequences. A literature search for articles published in the English language between 1970 and 2016 was conducted using MEDLINE, the Cochrane Library, Pubmed, Psychlit, Ovid, PsycINFO, and Proquest. The bibliographies of all included studies were also reviewed to identify additional relevant citations. A concept analysis was conducted on the literature findings using six stages of Walker and Avant's method. The concept analysis differentiated between suicide, lethality, suicidal behavior, and suicide lethality. Presence of a suicide plan or a written suicide note was not found to be associated with the majority of completed suicides included in the definition of suicide lethality. There are a few scales that measure the lethality of a suicide attempt, but none that attempt to measure the concept of suicide lethality as described in this analysis. Clarifying the concept of suicide lethality encourages awareness of the possibility of different suicidal behaviors associated with different suicide outcomes and will inform the development of future nursing interventions. A clearer definition of the concept of suicide lethality will guide clinical practice, research, and policy development aimed at suicide prevention.

  4. Subject-specific cardiovascular system model-based identification and diagnosis of septic shock with a minimally invasive data set: animal experiments and proof of concept

    International Nuclear Information System (INIS)

    Geoffrey Chase, J; Starfinger, Christina; Hann, Christopher E; Lambermont, Bernard; Ghuysen, Alexandre; Kolh, Philippe; Dauby, Pierre C; Desaive, Thomas; Shaw, Geoffrey M

    2011-01-01

    A cardiovascular system (CVS) model and parameter identification method have previously been validated for identifying different cardiac and circulatory dysfunctions in simulation and using porcine models of pulmonary embolism, hypovolemia with PEEP titrations and induced endotoxic shock. However, these studies required both left and right heart catheters to collect the data required for subject-specific monitoring and diagnosis—a maximally invasive data set in a critical care setting although it does occur in practice. Hence, use of this model-based diagnostic would require significant additional invasive sensors for some subjects, which is unacceptable in some, if not all, cases. The main goal of this study is to prove the concept of using only measurements from one side of the heart (right) in a 'minimal' data set to identify an effective patient-specific model that can capture key clinical trends in endotoxic shock. This research extends existing methods to a reduced and minimal data set requiring only a single catheter and reducing the risk of infection and other complications—a very common, typical situation in critical care patients, particularly after cardiac surgery. The extended methods and assumptions that found it are developed and presented in a case study for the patient-specific parameter identification of pig-specific parameters in an animal model of induced endotoxic shock. This case study is used to define the impact of this minimal data set on the quality and accuracy of the model application for monitoring, detecting and diagnosing septic shock. Six anesthetized healthy pigs weighing 20–30 kg received a 0.5 mg kg −1 endotoxin infusion over a period of 30 min from T0 to T30. For this research, only right heart measurements were obtained. Errors for the identified model are within 8% when the model is identified from data, re-simulated and then compared to the experimentally measured data, including measurements not used in the

  5. Clostridium sordellii lethal toxin kills mice by inducing a major increase in lung vascular permeability.

    Science.gov (United States)

    Geny, Blandine; Khun, Huot; Fitting, Catherine; Zarantonelli, Leticia; Mazuet, Christelle; Cayet, Nadège; Szatanik, Marek; Prevost, Marie-Christine; Cavaillon, Jean-Marc; Huerre, Michel; Popoff, Michel R

    2007-03-01

    When intraperitoneally injected into Swiss mice, Clostridium sordellii lethal toxin reproduces the fatal toxic shock syndrome observed in humans and animals after natural infection. This animal model was used to study the mechanism of lethal toxin-induced death. Histopathological and biochemical analyses identified lung and heart as preferential organs targeted by lethal toxin. Massive extravasation of blood fluid in the thoracic cage, resulting from an increase in lung vascular permeability, generated profound modifications such as animal dehydration, increase in hematocrit, hypoxia, and finally, cardiorespiratory failure. Vascular permeability increase induced by lethal toxin resulted from modifications of lung endothelial cells as evidenced by electron microscopy. Immunohistochemical analysis demonstrated that VE-cadherin, a protein participating in intercellular adherens junctions, was redistributed from membrane to cytosol in lung endothelial cells. No major sign of lethal toxin-induced inflammation was observed that could participate in the toxic shock syndrome. The main effect of the lethal toxin is the glucosylation-dependent inactivation of small GTPases, in particular Rac, which is involved in actin polymerization occurring in vivo in lungs leading to E-cadherin junction destabilization. We conclude that the cells most susceptible to lethal toxin are lung vascular endothelial cells, the adherens junctions of which were altered after intoxication.

  6. Theories of Lethal Mutagenesis: From Error Catastrophe to Lethal Defection.

    Science.gov (United States)

    Tejero, Héctor; Montero, Francisco; Nuño, Juan Carlos

    2016-01-01

    RNA viruses get extinct in a process called lethal mutagenesis when subjected to an increase in their mutation rate, for instance, by the action of mutagenic drugs. Several approaches have been proposed to understand this phenomenon. The extinction of RNA viruses by increased mutational pressure was inspired by the concept of the error threshold. The now classic quasispecies model predicts the existence of a limit to the mutation rate beyond which the genetic information of the wild type could not be efficiently transmitted to the next generation. This limit was called the error threshold, and for mutation rates larger than this threshold, the quasispecies was said to enter into error catastrophe. This transition has been assumed to foster the extinction of the whole population. Alternative explanations of lethal mutagenesis have been proposed recently. In the first place, a distinction is made between the error threshold and the extinction threshold, the mutation rate beyond which a population gets extinct. Extinction is explained from the effect the mutation rate has, throughout the mutational load, on the reproductive ability of the whole population. Secondly, lethal defection takes also into account the effect of interactions within mutant spectra, which have been shown to be determinant for the understanding the extinction of RNA virus due to an augmented mutational pressure. Nonetheless, some relevant issues concerning lethal mutagenesis are not completely understood yet, as so survival of the flattest, i.e. the development of resistance to lethal mutagenesis by evolving towards mutationally more robust regions of sequence space, or sublethal mutagenesis, i.e., the increase of the mutation rate below the extinction threshold which may boost the adaptability of RNA virus, increasing their ability to develop resistance to drugs (including mutagens). A better design of antiviral therapies will still require an improvement of our knowledge about lethal

  7. Shock absorber

    International Nuclear Information System (INIS)

    Nemeth, J.D.

    1981-01-01

    A shock absorber for the support of piping and components in a nuclear power plant is described. It combines a high degree of stiffness under sudden shocks, e.g. seismic disturbances, with the ability to allow for thermal expansion without resistance when so required. (JIW)

  8. Non-Lethal Weapons Program

    Science.gov (United States)

    Sheets Frequently Asked Questions Non-Lethal Weapons FAQs Active Denial System FAQs Human Electro -Muscular Incapacitation FAQs Related Links Business Opportunities Contact JNLWD Congressional Engagement , Wednesday, Sept 20, 2017. The Active Denial System, blunt-impact munitions, dazzling lasers, LRAD 100X

  9. demystifying the shock of shocking

    African Journals Online (AJOL)

    (with a pulse), atrial fibrillation and atrial flutter. The energy dose in cardioversion is less (0.5. - 2 J/kg) than in defibrillation (2 - 4 J/kg). In cardioversion the shock is discharged synchronously with the native R wave of the patient. Without synchronisation,. VF can be induced if a shock is delivered during the refractory period ...

  10. Hypovolemic shock

    Science.gov (United States)

    ... the person's position unless they are in immediate danger. Do not give fluids by mouth. If person ... the patient with shock. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine . 25th ed. Philadelphia, PA: ...

  11. Shock absorber

    International Nuclear Information System (INIS)

    Housman, J.J.

    1978-01-01

    A shock absorber is described for use in a hostile environment at the end of a blind passage for absorbing impact loads. The shock absorber includes at least one element which occupies the passage and which is comprised of a porous brittle material which is substantially non-degradable in the hostile environment. A void volume is provided in the element to enable the element to absorb a predetermined level of energy upon being crushed due to impact loading

  12. Synthesis and thermotolerance of heat shock proteins in Campylobacter jejuni

    International Nuclear Information System (INIS)

    Kim, C.K.; Kim, H.O.; Lee, K.J.

    1991-01-01

    The heat shock responses of Campylobacter jejuni were studied by examination of their survival rates and synthesis of heat shock proteins. When C. jejuni cells were treated at the sublethal temperatures of 48C° for 30 minutes, most of the cells maintained their viabilities and synthesized the heat shock proteins of 90, 73, and 66 kD in molecular weight. By the method of two-dimensional electrophoresis, the heat shock proteins of C. jejuni were identified to be Hsp90, Hsp73, and Hsp66. During the heat shock at 48C°, the heat shock proteins were induced from about 5 minutes after the heat shock treatment. Their synthesis was continued upto 30 minutes, but remarkably retarded after 50 minutes. When C. jejune cells were heat shocked at 51C° for 30 minutes, the survival rates of the cells were decreased by about 10 3 fold and synthesis of heat shock proteins and normal proteins was also generally retarded. The cells exposed to 55C° for 30 minutes died off by more than 10 5 cells and the new protein synthesis was not observed. But when C. jejuni cells were heat-shocked at the sublethal temperature of 48C° for 15 to 20 minutes and then were exposed at the lethal temperature of 55C° for 30 minutes, their viabilities were higher than those exposed at 55C° for 30 minutes without pre-heat shock at 48C°. Therefore, the heat shock proteins synthesized at the sublethal temperature of 48C° in C. jejuni were thought to be responsible for thermotolerance. However, when C. jejuni cells heat-shocked at various ranges of sublethal and lethal temperatures were placed back to the optimum temperature of 42C°, the multiplication patterns of the cells pretreated at different temperatures were not much different each other

  13. Toxic shock syndrome

    Science.gov (United States)

    Staphylococcal toxic shock syndrome; Toxic shock-like syndrome; TSLS ... Toxic shock syndrome is caused by a toxin produced by some types of staphylococcus bacteria. A similar problem, called toxic shock- ...

  14. Shock Waves

    CERN Document Server

    Jiang, Z

    2005-01-01

    The International Symposium on Shock Waves (ISSW) is a well established series of conferences held every two years in a different location. A unique feature of the ISSW is the emphasis on bridging the gap between physicists and engineers working in fields as different as gas dynamics, fluid mechanics and materials sciences. The main results presented at these meetings constitute valuable proceedings that offer anyone working in this field an authoritative and comprehensive source of reference.

  15. QTL mapping of inbreeding-related cold sensitivity and conditional lethality in Drosophila melanogaster

    DEFF Research Database (Denmark)

    Vermeulen, Corneel J.; Bijlsma, R.; Loeschcke, Volker

    2008-01-01

    of inbreeding-related and conditionally expressed lethality in Drosophila melanogaster. The lethal effect was triggered by exposure to a cold shock. We used a North Carolina crossing Design 3 to establish the mapping population, as well as to estimate the average dominance ratio and heritability. We found two......Inbreeding depression is a central theme within genetics, and is of specific interest for researchers within evolutionary and conservation genetics and animal and plant breeding. Inbreeding effects are thought to be caused by the joint expression of conditional and unconditional deleterious alleles....... Whenever the expression of deleterious alleles is conditional, this can result in extreme environmental sensitivity in certain inbred lineages. Analysis of conditional lethal effects can reveal some of the loci that are sensitive to inbreeding. We performed a QTL (quantitative trait locus) mapping study...

  16. Effect of lethal and sub-lethal concentrations of tobacco (Nicotiana ...

    African Journals Online (AJOL)

    Lethal and sub-lethal bioassays on Clarias gariepinus were conducted to evaluate the toxicity of tobacco (Nicotiana tobaccum) leaf dust on weight gain and haematological indices of Clarias gariepinus (mean weight 10.5±0.70g) in glass aquaria with aeration system. The concentrations used during the lethal exposure are: ...

  17. Errors in macromolecular synthesis after stress. A study of the possible protective role of the small heat shock proteinsBiochemistry

    NARCIS (Netherlands)

    Marin Vinader, L.

    2006-01-01

    The general goal of this thesis was to gain insight in what small heat shock proteins (sHsps) do with respect to macromolecular synthesis during a stressful situation in the cell. It is known that after a non-lethal heat shock, cells are better protected against a subsequent more severe heat shock,

  18. Shock Prevention

    Science.gov (United States)

    1978-01-01

    The electrician pictured is installing a General Electric Ground Fault Interrupter (GFI), a device which provides protection against electrical shock in the home or in industrial facilities. Shocks due to defective wiring in home appliances or other electrical equipment can cause severe burns, even death. As a result, the National Electrical Code now requires GFIs in all new homes constructed. This particular type of GFI employs a sensing element which derives from technology acquired in space projects by SCI Systems, Inc., Huntsville, Alabama, producer of sensors for GE and other manufacturers of GFI equipment. The sensor is based on the company's experience in developing miniaturized circuitry for space telemetry and other spacecraft electrical systems; this experience enabled SCI to package interruptor circuitry in the extremely limited space available and to produce sensory devices at practicable cost. The tiny sensor measures the strength of the electrical current and detects current differentials that indicate a fault in the functioning of an electrical system. The sensing element then triggers a signal to a disconnect mechanism in the GFI, which cuts off the current in the faulty circuit.

  19. Modulation of endotoxicity of Shigella generalized modules for membrane antigens (GMMA) by genetic lipid A modifications: relative activation of TLR4 and TLR2 pathways in different mutants.

    Science.gov (United States)

    Rossi, Omar; Pesce, Isabella; Giannelli, Carlo; Aprea, Susanna; Caboni, Mariaelena; Citiulo, Francesco; Valentini, Sara; Ferlenghi, Ilaria; MacLennan, Calman Alexander; D'Oro, Ugo; Saul, Allan; Gerke, Christiane

    2014-09-05

    Outer membrane particles from Gram-negative bacteria are attractive vaccine candidates as they present surface antigens in their natural context. We previously developed a high yield production process for genetically derived particles, called generalized modules for membrane antigens (GMMA), from Shigella. As GMMA are derived from the outer membrane, they contain immunostimulatory components, especially lipopolysaccharide (LPS). We examined ways of reducing their reactogenicity by modifying lipid A, the endotoxic part of LPS, through deletion of late acyltransferase genes, msbB or htrB, in GMMA-producing Shigella sonnei and Shigella flexneri strains. GMMA with resulting penta-acylated lipid A from the msbB mutants showed a 600-fold reduced ability, and GMMA from the S. sonnei ΔhtrB mutant showed a 60,000-fold reduced ability compared with GMMA with wild-type lipid A to stimulate human Toll-like receptor 4 (TLR4) in a reporter cell line. In human peripheral blood mononuclear cells, GMMA with penta-acylated lipid A showed a marked reduction in induction of inflammatory cytokines (S. sonnei ΔhtrB, 800-fold; ΔmsbB mutants, 300-fold). We found that the residual activity of these GMMA is largely due to non-lipid A-related TLR2 activation. In contrast, in the S. flexneri ΔhtrB mutant, a compensatory lipid A palmitoleoylation resulted in GMMA with hexa-acylated lipid A with ∼10-fold higher activity to stimulate peripheral blood mononuclear cells than GMMA with penta-acylated lipid A, mostly due to retained TLR4 activity. Thus, for use as vaccines, GMMA will likely require lipid A penta-acylation. The results identify the relative contributions of TLR4 and TLR2 activation by GMMA, which need to be taken into consideration for GMMA vaccine development. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

  20. Factors influencing circadian rhythms in acetaminophen lethality.

    Science.gov (United States)

    Schnell, R C; Bozigian, H P; Davies, M H; Merrick, B A; Park, K S; McMillan, D A

    1984-01-01

    Experiments were conducted to examine the effects of changes in lighting schedules and food consumption on circadian rhythms in acetaminophen lethality and hepatic glutathione levels in male mice. Under a normal lighting schedule (light: 06.00-18.00 h), male mice exhibited a circadian rhythm in acetaminophen lethality (peak: 18.00 h; nadir: 06.00, 10.00 h) and an inverse rhythm in hepatic glutathione concentrations (peak: 06.00, 10.00 h; nadir: 18.00 h). Under a reversed lighting schedule (light: 18.00-06.00 h) the glutathione rhythm was reversed and the rhythm in acetaminophen lethality was altered showing greater sensitivity to the drug. Under continuous light, there was a shift in the acetaminophen lethality and the hepatic glutathione rhythms. Under continuous dark, both rhythms were abolished. Under a normal lighting regimen, hepatic glutathione levels were closely correlated with food consumption; i.e., both were increased during the dark phase and decreased during the light phase. Fasting the mice for 12 h abolished the rhythms in acetaminophen lethality and hepatic glutathione levels; moreover, the lethality was increased and the hepatic glutathione levels were decreased. These experiments show that both lighting schedules and feeding can alter the circadian rhythms in acetaminophen lethality and hepatic glutathione levels in male mice.

  1. Transporting Patients with Lethal Contagious Infections

    National Research Council Canada - National Science Library

    Swartz, Colleen

    2002-01-01

    .... The AIT is a unique military medical team capable of worldwide air evacuation and management of a limited number of patients who are potentially exposed to known and unknown lethal communicable...

  2. Experiences in therapy for lethal midline granuloma

    International Nuclear Information System (INIS)

    Tosaka, Kaoru; Ishikawa, Takeru

    1982-01-01

    Four cases of the lethal midline granuloma or malignant granuloma of the nose were treated by irradiation and chemotherapy, which are generally prescribed for malignant lymphomas. Clinical, histological and laboratory examination indicated that they were the lethal midline granuloma and clearly differentiated from Wegener's granulomatosis or malignant lymphoma. All of the cases exhibited primary remission. The four cases were observed up to 38, 22, 14, and 10 months since the beginning of the therapy, showing no local or general recurrence. (author)

  3. Collisionless electrostatic shocks

    DEFF Research Database (Denmark)

    Andersen, H.K.; Andersen, S.A.; Jensen, Vagn Orla

    1970-01-01

    An attempt was made in the laboratory to observe the standing collisionless electrostatic shocks in connection with the bow shock of the earth......An attempt was made in the laboratory to observe the standing collisionless electrostatic shocks in connection with the bow shock of the earth...

  4. Geometrical shock dynamics for magnetohydrodynamic fast shocks

    KAUST Repository

    Mostert, W.; Pullin, D. I.; Samtaney, Ravi; Wheatley, V.

    2016-01-01

    We describe a formulation of two-dimensional geometrical shock dynamics (GSD) suitable for ideal magnetohydrodynamic (MHD) fast shocks under magnetic fields of general strength and orientation. The resulting area–Mach-number–shock-angle relation is then incorporated into a numerical method using pseudospectral differentiation. The MHD-GSD model is verified by comparison with results from nonlinear finite-volume solution of the complete ideal MHD equations applied to a shock implosion flow in the presence of an oblique and spatially varying magnetic field ahead of the shock. Results from application of the MHD-GSD equations to the stability of fast MHD shocks in two dimensions are presented. It is shown that the time to formation of triple points for both perturbed MHD and gas-dynamic shocks increases as (Formula presented.), where (Formula presented.) is a measure of the initial Mach-number perturbation. Symmetry breaking in the MHD case is demonstrated. In cylindrical converging geometry, in the presence of an azimuthal field produced by a line current, the MHD shock behaves in the mean as in Pullin et al. (Phys. Fluids, vol. 26, 2014, 097103), but suffers a greater relative pressure fluctuation along the shock than the gas-dynamic shock. © 2016 Cambridge University Press

  5. Geometrical shock dynamics for magnetohydrodynamic fast shocks

    KAUST Repository

    Mostert, W.

    2016-12-12

    We describe a formulation of two-dimensional geometrical shock dynamics (GSD) suitable for ideal magnetohydrodynamic (MHD) fast shocks under magnetic fields of general strength and orientation. The resulting area–Mach-number–shock-angle relation is then incorporated into a numerical method using pseudospectral differentiation. The MHD-GSD model is verified by comparison with results from nonlinear finite-volume solution of the complete ideal MHD equations applied to a shock implosion flow in the presence of an oblique and spatially varying magnetic field ahead of the shock. Results from application of the MHD-GSD equations to the stability of fast MHD shocks in two dimensions are presented. It is shown that the time to formation of triple points for both perturbed MHD and gas-dynamic shocks increases as (Formula presented.), where (Formula presented.) is a measure of the initial Mach-number perturbation. Symmetry breaking in the MHD case is demonstrated. In cylindrical converging geometry, in the presence of an azimuthal field produced by a line current, the MHD shock behaves in the mean as in Pullin et al. (Phys. Fluids, vol. 26, 2014, 097103), but suffers a greater relative pressure fluctuation along the shock than the gas-dynamic shock. © 2016 Cambridge University Press

  6. Caffeine and D sub 2 O medium interact in affecting the expression of radiation-induced potentially lethal damage

    Energy Technology Data Exchange (ETDEWEB)

    Utsumi, H. (Kyoto Univ. (Japan). Radiation Biology Center); Elkind, M.M. (Colorado State Univ., Fort Collins, CO (United States). Dept. of Radiological Health Sciences)

    1991-10-01

    Earlier work has been extended to compare the killing of long-phase V79 Chinese hamster cells by ionizing radiation when they are treated immediately after irradiation with medium containing either caffeine or 90% D{sub 2}O. The object was to determine if the enhanced killing due to post-treatment with caffeine, or D{sub 2}O, resulted from action on the same sector of potentially lethal damage as appeared to be the case for hypertonic shock and D{sub 2}O medium. The treatments by themselves were not toxic to unirradiated cells. We found that the enhanced expression of potentially lethal damage by post-treatment with caffeine or D{sub 2}O medium is similar. For example, the kinetic of the repair of the potentially lethal damage expressible by either post-treatment was similar, and an additive enhancement of potentially lethal damage occurred when the two treatments were administered sequentially. These findings suggest that caffeine and D{sub 2}O medium affect the same sector of potentially lethal damage. When the two treatments were combined, however, they competed with each other. Thus, although caffeine and D{sub 2}O medium act on the same sector of potentially lethal damage they do so differently, suggesting that more than one pathway of the expression of radiation damage can result in the same phenotypic effect. (author).

  7. Caffeine and D2O medium interact in affecting the expression of radiation-induced potentially lethal damage

    International Nuclear Information System (INIS)

    Utsumi, H.; Elkind, M.M.

    1991-01-01

    Earlier work has been extended to compare the killing of long-phase V79 Chinese hamster cells by ionizing radiation when they are treated immediately after irradiation with medium containing either caffeine or 90% D 2 O. The object was to determine if the enhanced killing due to post-treatment with caffeine, or D 2 O, resulted from action on the same sector of potentially lethal damage as appeared to be the case for hypertonic shock and D 2 O medium. The treatments by themselves were not toxic to unirradiated cells. We found that the enhanced expression of potentially lethal damage by post-treatment with caffeine or D 2 O medium is similar. For example, the kinetic of the repair of the potentially lethal damage expressible by either post-treatment was similar, and an additive enhancement of potentially lethal damage occurred when the two treatments were administered sequentially. These findings suggest that caffeine and D 2 O medium affect the same sector of potentially lethal damage. When the two treatments were combined, however, they competed with each other. Thus, although caffeine and D 2 O medium act on the same sector of potentially lethal damage they do so differently, suggesting that more than one pathway of the expression of radiation damage can result in the same phenotypic effect. (author)

  8. Lethality Index 2008-2014: Less shootings, same lethality, more opacity

    Directory of Open Access Journals (Sweden)

    Carlos Silva Forné

    2017-11-01

    Full Text Available This article evaluates the use of lethal force by Mexican federal security forces during shootings with presumed members of organized crime from 2008-2014. The authors use official data and press reports on deaths and wounded in shootings to construct indicators such as the number of dead civilians over the number of dead officials from the federal security forces and the number of dead civilians over the number of wounded civilians. In a context where certain factors that contribute to an excessive use of force become more common, the results of the study show a growing use of lethal force. This raises questions over the possible excessive use of lethal force as a normal or systematic practice. The study also shows a growing context of opacity in the information available to evaluate the use of lethal force and the general lack of a legal framework to regulate the use of lethal force in Mexico.

  9. Miniature shock tube for laser driven shocks.

    Science.gov (United States)

    Busquet, Michel; Barroso, Patrice; Melse, Thierry; Bauduin, Daniel

    2010-02-01

    We describe in this paper the design of a miniature shock tube (smaller than 1 cm(3)) that can be placed in a vacuum vessel and allows transverse optical probing and longitudinal backside extreme ultraviolet emission spectroscopy in the 100-500 A range. Typical application is the study of laser launched radiative shocks, in the framework of what is called "laboratory astrophysics."

  10. Are Credit Shocks Supply or Demand Shocks?

    OpenAIRE

    Bijapur, Mohan

    2013-01-01

    This paper provides new insights into the relationship between the supply of credit and the macroeconomy. We present evidence that credit shocks constitute shocks to aggregate supply in that they have a permanent effect on output and cause inflation to rise in the short term. Our results also suggest that the effects on aggregate supply have grown stronger in recent decades.

  11. Shock absorbing structure

    International Nuclear Information System (INIS)

    Kojima, Naoki; Matsushita, Kazuo.

    1992-01-01

    Small pieces of shock absorbers are filled in a space of a shock absorbing vessel which is divided into a plurality of sections by partitioning members. These sections function to prevent excess deformation or replacement of the fillers upon occurrence of falling accident. Since the shock absorbing small pieces in the shock absorbing vessel are filled irregularly, shock absorbing characteristics such as compression strength is not varied depending on the direction, but they exhibit excellent shock absorbing performance. They surely absorb shocks exerted on a transportation vessel upon falling or the like. If existing artificial fillers such as pole rings made of metal or ceramic and cut pieces such as alumium extrusion molding products are used as the shock absorbing pieces, they have excellent fire-proofness and cold resistance since the small pieces are inflammable and do not contain water. (T.M.)

  12. Melting under shock compression

    International Nuclear Information System (INIS)

    Bennett, B.I.

    1980-10-01

    A simple model, using experimentally measured shock and particle velocities, is applied to the Lindemann melting formula to predict the density, temperature, and pressure at which a material will melt when shocked from room temperature and zero pressure initial conditions

  13. Genetics Home Reference: Amish lethal microcephaly

    Science.gov (United States)

    ... 1 in 500 newborns in the Old Order Amish population of Pennsylvania. It has not been found outside this population. Related Information What information about a genetic condition can statistics provide? Why are some genetic ... gene cause Amish lethal microcephaly . The SLC25A19 gene provides instructions for ...

  14. The evolution of lethal intergroup violence

    OpenAIRE

    Kelly, Raymond C.

    2005-01-01

    Recent findings and analyses in evolutionary biology, archaeology, and ethnology provide a favorable conjuncture for examining the evolution of lethal intergroup violence among hominids during the 2.9-million-year Paleolithic time span. Here, I seek to identify and investigate the main turning points in this evolutionary trajectory and to delineate the periodization that follows from this inquiry.

  15. The evolution of lethal intergroup violence.

    Science.gov (United States)

    Kelly, Raymond C

    2005-10-25

    Recent findings and analyses in evolutionary biology, archaeology, and ethnology provide a favorable conjuncture for examining the evolution of lethal intergroup violence among hominids during the 2.9-million-year Paleolithic time span. Here, I seek to identify and investigate the main turning points in this evolutionary trajectory and to delineate the periodization that follows from this inquiry.

  16. A new lethal sclerosing bone dysplasia

    International Nuclear Information System (INIS)

    Kingston, H.M.; Freeman, J.S.; Hall, C.M.

    1991-01-01

    A neonate is described with a lethal sclerosing bone dysplasia associated with prenatal fractures and craniofacial abnormalities including microcephaly, exophthalmos, hypoplastic nose and mid-face, small jaw and nodular hyperplasia of the gums. Parental consanguinity suggests that an autosomal recessive mutation is the likely aetiology. (orig.)

  17. Biomass shock pretreatment

    Science.gov (United States)

    Holtzapple, Mark T.; Madison, Maxine Jones; Ramirez, Rocio Sierra; Deimund, Mark A.; Falls, Matthew; Dunkelman, John J.

    2014-07-01

    Methods and apparatus for treating biomass that may include introducing a biomass to a chamber; exposing the biomass in the chamber to a shock event to produce a shocked biomass; and transferring the shocked biomass from the chamber. In some aspects, the method may include pretreating the biomass with a chemical before introducing the biomass to the chamber and/or after transferring shocked biomass from the chamber.

  18. Relativistic Shock Acceleration

    International Nuclear Information System (INIS)

    Duffy, P.; Downes, T.P.; Gallant, Y.A.; Kirk, J.G.

    1999-01-01

    In this paper we briefly review the basic theory of shock waves in relativistic hydrodynamics and magneto-hydrodynamics, emphasising some astrophysically interesting cases. We then present an overview of the theory of particle acceleration at such shocks describing the methods used to calculate the spectral indices of energetic particles. Recent results on acceleration at ultra-relativistic shocks are discussed. (author)

  19. Alfven shock trains

    International Nuclear Information System (INIS)

    Malkov, M.A.; Kennel, C.F.; Wu, C.C.; Pellat, R.; Shapiro, V.D.

    1991-01-01

    The Cohen--Kulsrud--Burgers equation (CKB) is used to consider the nonlinear evolution of resistive, quasiparallel Alfven waves subject to a long-wavelength, plane-polarized, monochromatic instability. The instability saturates by nonlinear steepening, which proceeds until the periodic waveform develops an interior scale length comparable to the dissipation length; a fast or an intermediate shock then forms. The result is a periodic train of Alfven shocks of one or the other type. For propagation strictly parallel to the magnetic field, there will be two shocks per instability wavelength. Numerical integration of the time-dependent CKB equation shows that an initial, small-amplitude growing wave asymptotes to a stable, periodic stationary wave whose analytic solution specifies how the type of shock embedded in the shock train, and the amplitude and speed of the shock train, depend on the strength and phase of the instability. Waveforms observed upstream of the Earth's bowshock and cometary shocks resemble those calculated here

  20. Protection against septic shock and suppression of tumor necrosis factor alpha and nitric oxide production on macrophages and microglia by a standard aqueous extract of Mangifera indica L. (VIMANG). Role of mangiferin isolated from the extract.

    Science.gov (United States)

    Garrido, Gabino; Delgado, René; Lemus, Yeny; Rodríguez, Janet; García, Dagmar; Núñez-Sellés, Alberto J

    2004-08-01

    The present study illustrates the effects of a standard aqueous extract, used in Cuba under the brand name of VIMANG, from the stem bark of Mangifera indica L. on the production of tumor necrosis factor alpha (TNFalpha) and nitric oxide (NO) in in vivo and in vitro experiments. In vivo was determined by the action of the extract and its purified glucosylxanthone (mangiferin) on TNFalpha in a murine model of endotoxic shock using Balb/c mice pre-treated with lipopolysaccharide (LPS) 0.125 mg kg(-1), i.p. In vitro, M. indica extract and mangiferin were tested on TNFalpha and NO production in activated macrophages (RAW264.7 cell line) and microglia (N9 cell line) stimulated with LPS (10ng ml(-1)) and interferon gamma (IFNgamma, 2U ml(-1)). M. indica extract reduced dose-dependently TNFalpha production in the serum (ED50 = 64.5 mg kg(-1)) and the TNFalpha mRNA expression in the lungs and livers of mice. Mangiferin also inhibited systemic TNFalpha at 20 mg kg(-1). In RAW264.7, the extract inhibited TNFalpha (IC50 = 94.1 microg ml(-1)) and NO (IC50 = 64.4 microg ml(-1)). In microglia the inhibitions of the extract were IC50 = 76.0 microg ml(-1) (TNFalpha) and 84.0 microg ml(-1) (NO). These findings suggest that the anti-inflammatory response observed during treatment with M. indica extract must be related with inhibition of TNFalpha and NO production. Mangiferin, a main component in the extract, is involved in these effects. The TNFalpha and NO inhibitions by M. indica extract and mangiferin on endotoxic shock and microglia are reported here for the first time. Copyright 2004 Elsevier Ltd.

  1. Lethal neonatal short-limbed dwarfism

    International Nuclear Information System (INIS)

    Kim, Ok Hwa; Yim, Chung Ik; Bahk, Yong Whee

    1986-01-01

    We have detailed our experiences on 6 cases of neonatal lethal short-limbed dwarfism and reviewed the articles. They include, achondrogenesis, thanatophoric dysplasia, asphyxiating thoracic dysplasia, osteogenesis imperfect a congenita, and hypophosphatasia lethals. Five babies were born alive but died soon after birth and one was a stillbirth. The main cause of failure to thrive was respiratory insufficiency. Each case was having quite characteristic radiologic findings, even if the general appearances were similar to the achondroplasts clinically. Precise diagnosis is very important for genetic counselling of the parents and alarm to them the possibility of bone dysplasias to the next offsprings. For this purpose, the radiologists play major role for the correct diagnosis. We stress that when the baby is born with short-limbed dwarfism, whole body radiogram should be taken including lateral view and postmortem radiogram is also very precious.

  2. Lethal neonatal short-limbed dwarfism

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ok Hwa; Yim, Chung Ik; Bahk, Yong Whee [Catholic Medical College, Seoul (Korea, Republic of)

    1986-02-15

    We have detailed our experiences on 6 cases of neonatal lethal short-limbed dwarfism and reviewed the articles. They include, achondrogenesis, thanatophoric dysplasia, asphyxiating thoracic dysplasia, osteogenesis imperfect a congenita, and hypophosphatasia lethals. Five babies were born alive but died soon after birth and one was a stillbirth. The main cause of failure to thrive was respiratory insufficiency. Each case was having quite characteristic radiologic findings, even if the general appearances were similar to the achondroplasts clinically. Precise diagnosis is very important for genetic counselling of the parents and alarm to them the possibility of bone dysplasias to the next offsprings. For this purpose, the radiologists play major role for the correct diagnosis. We stress that when the baby is born with short-limbed dwarfism, whole body radiogram should be taken including lateral view and postmortem radiogram is also very precious.

  3. Mining of lethal recessive genetic variation in Danish cattle

    DEFF Research Database (Denmark)

    Das, Ashutosh

    2015-01-01

    in fertility. The primary objective of this PhD projekt was to identify recessive lethal gentic variants in the main Danish dairy cattle breed. Holstein-Friesian utilzing next generation sequencing (NGS) data. This study shows a potential for the use of the NGS-based reverse genetic approach in identifying...... lethal or semi-lethal recessive gentic variation...

  4. Lethal midline granuloma syndrome: a diagnostic dilemma

    International Nuclear Information System (INIS)

    Ribeiro, Bruno Niemeyer de Freitas; Bahia, Paulo Roberto Valle; Oliveira, Ana Luiza Vianna Sobral de Magalhaes; Marchon Junior, Joao Luiz

    2012-01-01

    The rare lethal midline granuloma syndrome is difficult to diagnose because of the wide array of related diseases and lack of knowledge by the majority of physicians. In the present report, the authors describe the case of a patient with this disease, caused by squamous cell carcinoma, drawing attention to differential diagnoses and to clinical and radiological findings that may be useful to define the diagnosis. (author)

  5. Lethal Interpersonal Violence in the Middle Pleistocene

    OpenAIRE

    Sala, Nohemi; Arsuaga, Juan Luis; Pantoja-P?rez, Ana; Pablos, Adri?n; Mart?nez, Ignacio; Quam, Rolf M.; G?mez-Olivencia, Asier; Berm?dez de Castro, Jos? Mar?a; Carbonell, Eudald

    2015-01-01

    Evidence of interpersonal violence has been documented previously in Pleistocene members of the genus Homo, but only very rarely has this been posited as the possible manner of death. Here we report the earliest evidence of lethal interpersonal violence in the hominin fossil record. Cranium 17 recovered from the Sima de los Huesos Middle Pleistocene site shows two clear perimortem depression fractures on the frontal bone, interpreted as being produced by two episodes of localized blunt force ...

  6. Lethal midline granuloma syndrome: a diagnostic dilemma

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro, Bruno Niemeyer de Freitas; Bahia, Paulo Roberto Valle [Radiology, Hospital Universitario Clementino Fraga Filho - Universidade Federal do Rio de Janeiro (HUCFF-UFRJ), Rio de Janeiro, RJ (Brazil); Oliveira, Ana Luiza Vianna Sobral de Magalhaes [Resident of Medical Practice, Hospital Federal da Lagoa, Rio de Janeiro, RJ (Brazil); Marchon Junior, Joao Luiz [Unit of Computed Tomography, Hospital Federal da Lagoa, Rio de Janeiro, RJ (Brazil)

    2012-11-15

    The rare lethal midline granuloma syndrome is difficult to diagnose because of the wide array of related diseases and lack of knowledge by the majority of physicians. In the present report, the authors describe the case of a patient with this disease, caused by squamous cell carcinoma, drawing attention to differential diagnoses and to clinical and radiological findings that may be useful to define the diagnosis. (author)

  7. System Shock: The Archetype of Operational Shock

    Science.gov (United States)

    2017-05-25

    the battle space. They can also facilitate a much greater understanding of the variables involved in each party’s decision - making process. However...system shock nests within current US Army Unified Land Operations doctrine. In order to test the utility of system shock theory to Gray Zone...23 Neil E. Harrison, “Thinking about the World We Make ” in Chaos Theory in the Social Sciences: Foundations and Applications

  8. Lethal interpersonal violence in the Middle Pleistocene.

    Directory of Open Access Journals (Sweden)

    Nohemi Sala

    Full Text Available Evidence of interpersonal violence has been documented previously in Pleistocene members of the genus Homo, but only very rarely has this been posited as the possible manner of death. Here we report the earliest evidence of lethal interpersonal violence in the hominin fossil record. Cranium 17 recovered from the Sima de los Huesos Middle Pleistocene site shows two clear perimortem depression fractures on the frontal bone, interpreted as being produced by two episodes of localized blunt force trauma. The type of injuries, their location, the strong similarity of the fractures in shape and size, and the different orientations and implied trajectories of the two fractures suggest they were produced with the same object in face-to-face interpersonal conflict. Given that either of the two traumatic events was likely lethal, the presence of multiple blows implies an intention to kill. This finding shows that the lethal interpersonal violence is an ancient human behavior and has important implications for the accumulation of bodies at the site, supporting an anthropic origin.

  9. Lethal interpersonal violence in the Middle Pleistocene.

    Science.gov (United States)

    Sala, Nohemi; Arsuaga, Juan Luis; Pantoja-Pérez, Ana; Pablos, Adrián; Martínez, Ignacio; Quam, Rolf M; Gómez-Olivencia, Asier; Bermúdez de Castro, José María; Carbonell, Eudald

    2015-01-01

    Evidence of interpersonal violence has been documented previously in Pleistocene members of the genus Homo, but only very rarely has this been posited as the possible manner of death. Here we report the earliest evidence of lethal interpersonal violence in the hominin fossil record. Cranium 17 recovered from the Sima de los Huesos Middle Pleistocene site shows two clear perimortem depression fractures on the frontal bone, interpreted as being produced by two episodes of localized blunt force trauma. The type of injuries, their location, the strong similarity of the fractures in shape and size, and the different orientations and implied trajectories of the two fractures suggest they were produced with the same object in face-to-face interpersonal conflict. Given that either of the two traumatic events was likely lethal, the presence of multiple blows implies an intention to kill. This finding shows that the lethal interpersonal violence is an ancient human behavior and has important implications for the accumulation of bodies at the site, supporting an anthropic origin.

  10. Significance of production of peptide leukotrienes in murine traumatic shock

    International Nuclear Information System (INIS)

    Craft, D.V.; Lefer, D.J.; Hock, C.E.; Lefer, A.M.

    1986-01-01

    The authors studied the formation of a leukotriene metabolite in plasma and bile during traumatic shock. Anesthetized rats subjected to Noble-Collip drum trauma developed a lethal shock state characterized by a survival time of 1.9 +/- 0.3h, a 4.5-fold increase in plasma cathepsin D activity, and a reduction in mean arterial blood pressure to 45 +/- 2 mmHg compared with 108 +/- 5 mmHg in sham-shock controls. Plasma and bile samples were analyzed by reverse-phase high-pressure liquid chromatography (HPLC) for peptide leukotrienes, and their retention times were confirmed by co-elution with radioactive standards, radioimmunoassay (RIA), and UV spectrophotometry. No leukotrienes or metabolites were found in plasma. The major peptide leukotriene from bile was eluted between LTC 4 and LTD 4 and corresponds to a metabolite of LTE 4 , N-acetyl-LTE 4 , which is also produced during endotoxin shock. The metabolite increased nearly sevenfold in traumatic shock compared with sham trauma. The identity of the metabolite was confirmed by UV scan, which revealed a spectrum consistent with a peptide leukotriene and similar to that of previously reported spectra for N-acetyl-LTE 4 . In conclusion, peptide leukotrienes are rapidly cleared from the blood and appear in the bile as N-acetyl-LTE 4 , a metabolite of the peptide leukotrienes. These findings support a role of the peptide leukotrienes in the pathogenesis of traumatic shock

  11. Heat shock modulates the subcellular localization, stability, and activity of HIPK2

    International Nuclear Information System (INIS)

    Upadhyay, Mamta; Bhadauriya, Pratibha; Ganesh, Subramaniam

    2016-01-01

    The homeodomain-interacting protein kinase-2 (HIPK2) is a highly conserved serine/threonine kinase and is involved in transcriptional regulation. HIPK2 is a highly unstable protein, and is kept at a low level under normal physiological conditions. However, exposure of cells to physiological stress – such as hypoxia, oxidative stress, or UV damage – is known to stabilize HIPK2, leading to the HIPK2-dependent activation of p53 and the cell death pathway. Therefore HIPK2 is also known as a stress kinase and as a stress-activated pro-apoptotic factor. We demonstrate here that exposure of cells to heat shock results in the stabilization of HIPK2 and the stabilization is mediated via K63-linked ubiquitination. Intriguingly, a sub-lethal heat shock (42 °C, 1 h) results in the cytoplasmic localization of HIPK2, while a lethal heat shock (45 °C, 1 h) results in its nuclear localization. Cells exposed to the lethal heat shock showed significantly higher levels of the p53 activity than those exposed to the sub-lethal thermal stress, suggesting that both the level and the nuclear localization are essential for the pro-apoptotic activity of HIPK2 and that the lethal heat shock could retain the HIPK2 in the nucleus to promote the cell death. Taken together our study underscores the importance of HIPK2 in stress mediated cell death, and that the HIPK2 is a generic stress kinase that gets activated by diverse set of physiological stressors.

  12. Heat shock modulates the subcellular localization, stability, and activity of HIPK2

    Energy Technology Data Exchange (ETDEWEB)

    Upadhyay, Mamta; Bhadauriya, Pratibha; Ganesh, Subramaniam, E-mail: sganesh@iitk.ac.in

    2016-04-15

    The homeodomain-interacting protein kinase-2 (HIPK2) is a highly conserved serine/threonine kinase and is involved in transcriptional regulation. HIPK2 is a highly unstable protein, and is kept at a low level under normal physiological conditions. However, exposure of cells to physiological stress – such as hypoxia, oxidative stress, or UV damage – is known to stabilize HIPK2, leading to the HIPK2-dependent activation of p53 and the cell death pathway. Therefore HIPK2 is also known as a stress kinase and as a stress-activated pro-apoptotic factor. We demonstrate here that exposure of cells to heat shock results in the stabilization of HIPK2 and the stabilization is mediated via K63-linked ubiquitination. Intriguingly, a sub-lethal heat shock (42 °C, 1 h) results in the cytoplasmic localization of HIPK2, while a lethal heat shock (45 °C, 1 h) results in its nuclear localization. Cells exposed to the lethal heat shock showed significantly higher levels of the p53 activity than those exposed to the sub-lethal thermal stress, suggesting that both the level and the nuclear localization are essential for the pro-apoptotic activity of HIPK2 and that the lethal heat shock could retain the HIPK2 in the nucleus to promote the cell death. Taken together our study underscores the importance of HIPK2 in stress mediated cell death, and that the HIPK2 is a generic stress kinase that gets activated by diverse set of physiological stressors.

  13. Hydraulic shock absorbers

    International Nuclear Information System (INIS)

    Thatcher, G.; Davidson, D. F.

    1984-01-01

    A hydraulic shock absorber of the dash pot kind for use with electrically conducting liquid such as sodium, has magnet means for electro magnetically braking a stream of liquid discharged from the cylinder. The shock absorber finds use in a liquid metal cooled nuclear reactor for arresting control rods

  14. Our Favorite Film Shocks

    DEFF Research Database (Denmark)

    Willerslev, Rane; Suhr, Christian

    2014-01-01

    The modern medium of film has long been hailed for its capacity for producing shocks of an entertaining, thought-provoking, or even politically emancipative nature. But what is a shock, how and when does it occur, how long does it last, and are there particular techniques for producing cinematic...

  15. Climate shocks and conflict

    NARCIS (Netherlands)

    Papaioannou, Kostadis J.

    2016-01-01

    This paper offers a historical micro-level analysis of the impact of climate shocks on the incidence of civil conflict in colonial Nigeria (1912-1945). Primary historical sources on court cases, prisoners and homicides are used to capture conflict. To measure climate shocks we use the deviation

  16. Lethal congenital contracture syndrome (LCCS) and other lethal arthrogryposes in Finland--an epidemiological study.

    Science.gov (United States)

    Pakkasjärvi, Niklas; Ritvanen, Annukka; Herva, Riitta; Peltonen, Leena; Kestilä, Marjo; Ignatius, Jaakko

    2006-09-01

    Arthrogryposis multiplex congenita is a heterogeneous group of disorders characterized by multiple contractures with an estimated frequency of 1 in 3,000 births. With improving diagnostic methods, increasing numbers of fetuses with arthrogryposis are found. The pathogenetic mechanisms are relatively well known but the epidemiology and genetics of the prenatally lethal forms of arthrogryposis are less well known. In this study we collected all cases of a multiple contractures diagnosed in Finland during 1987-2002 including live born infants, stillbirths, and terminated pregnancies. Ninety-two cases of 214 suffered intrauterine demise (68 selective pregnancy terminations and 24 stillbirths) and 58 died in infancy. In 141 out of these cases the diagnosis could be included within lethal arthrogryposes, with a prevalence of 1 in 6,985 (1.43/10,000) births. Of these, 59 had spinal cord pathology at autopsy and thus were of neurogenic origin. Thirty-nine cases had lethal congenital contracture syndrome (LCCS) clinically characterized by total immobility of the fetus at all ultrasound examinations (12 weeks or later), multiple joint contractures in both upper and lower limbs, hydrops, and fetal death before the 32nd week of pregnancy. LCCS is noted as a unique Finnish disorder with a prevalence of 1 in 25,250 (0.40/10,000) births and is a major cause of lethal arthrogryposis in Finland.

  17. Suicide Intent and Accurate Expectations of Lethality: Predictors of Medical Lethality of Suicide Attempts

    Science.gov (United States)

    Brown, Gregory K.; Henriques, Gregg R.; Sosdjan, Daniella; Beck, Aaron T.

    2004-01-01

    The degree of intent to commit suicide and the severity of self-injury were examined in individuals (N = 180) who had recently attempted suicide. Although a minimal association was found between the degree of suicide intent and the degree of lethality of the attempt, the accuracy of expectations about the likelihood of dying was found to moderate…

  18. Potentially lethal damage and its repair

    International Nuclear Information System (INIS)

    Utsumi, Hiroshi

    1989-01-01

    Two forms termed fast-and slow-potentially lethal lethal damage (PLD) are introduced and discussed. The effect on the survival of x-irradiated Chinese hamster cells (V79) of two different post-treatments is examined in plateau- and in log-phases of growth. The postirradiation treatments used : a) incubation in hypertonic solution, and b) incubation in conditioned medium obtained from plateau-phase. Similar reduction in survival was caused by postirradiation treatment with hypertonic phosphate buffered saline, and similar increased in survival was effected by treatment in conditioned medium in plateau- and in log-phases cells. However, repair of PLD sensitive to hypertonic treatment was faster (half time, 5-10 min)(f-PLD repair) and independent from the repair of PLD (half time, 1-2 hour)(s-PLD repair) observed in conditioned medium. The results indicate the induction of two forms of PLD by radiation. Induction of both PLD was found to decrease with increasing LET of the radiation used. Identification of the molecular processes underlying repair and fixation of PLD is a task of particular interest, since it may allow replacement of a phenomenological definition with a molecular definition. Evidence is reviewed indicating the DNA double strand breaks (directly or indirectly induced) may be the DNA lesions underlying PLD. (author)

  19. Lethal domestic violence in eastern North Carolina.

    Science.gov (United States)

    Gilliland, M G; Spence, P R; Spence, R L

    2000-01-01

    Strategies for preventing domestic violence can be tailored to a particular geographic or socioeconomic area if the patterns of domestic violence in the area are known. National statistics, although widely available, may not be applicable to a specific region. We reviewed homicide deaths in Eastern North Carolina between 1978 and 1999 to identify patterns in this rural area. Approximately 20% of the homicide deaths in eastern North Carolina are caused by intimate partners. Women accounted for 53% of the victims in 1976, similar to national figures but not rising to 72% as seen nationally in 1998. Latinos are an increasing presence in the area, but had only one recorded episode of lethal violence against an intimate partner. Gunshots accounted for most of the deaths (59% in men, 72% in women). Knowledge of such patterns can assist in selecting prevention strategies for this particular area. Over the last 25 years increasing attention has been devoted to domestic violence (DV), initially defined as abuse committed against a spouse, former spouse, fiancée, boy- or girlfriend, or cohabitant. As time has passed, the definition has been broadened to include other family members--elders, children, and siblings. The Centers for Disease Control and Prevention (CDC) now uses the term "intimate partner violence" for intentional emotional or physical abuse inflicted by a spouse, ex-spouse, a present or former boy- or girlfriend, or date. For the purposes of this paper, we consider DV interchangeable with intimate partner violence. There has been a national concern that abusive events are under-reported. The National Crime Victimization Survey, an anonymous household survey, indicated nearly 1 million incidents of non-lethal intimate partner violence per year between 1992 and 1996. The number decreased from 1.1 million in 1993 to 840,000 in 1996. Attempts to validate such data for a given geographic area often require subjects to violate anonymity--this may account for lower

  20. Sodium lactate improves renal microvascular thrombosis compared to sodium bicarbonate and 0.9% NaCl in a porcine model of endotoxic shock: an experimental randomized open label controlled study.

    Science.gov (United States)

    Duburcq, Thibault; Durand, Arthur; Tournoys, Antoine; Gnemmi, Viviane; Gmyr, Valery; Pattou, François; Jourdain, Mercedes; Tamion, Fabienne; Besnier, Emmanuel; Préau, Sebastien; Parmentier-Decrucq, Erika; Mathieu, Daniel; Poissy, Julien; Favory, Raphaël

    2018-02-14

    Sodium lactate seemed to improve fluid balance and avoid fluid overload. The objective of this study was to determine if these beneficial effects can be at least partly explained by an improvement in disseminated intravascular coagulation (DIC)-associated renal microvascular thrombosis. Ancillary work of an interventional randomized open label controlled experimental study. Fifteen female "Large White" pigs (2 months old) were challenged with intravenous infusion of E. coli endotoxin. Three groups of five animals were randomly assigned to receive different fluids: a treatment group received sodium lactate 11.2% (SL group); an isotonic control group received 0.9% NaCl (NC group); a hypertonic control group, with the same amount of osmoles and sodium than SL group, received sodium bicarbonate 8.4% (SB group). Glomerular filtration rate (GFR) markers, coagulation and inflammation parameters were measured over a 5-h period. Immediately after euthanasia, kidneys were withdrawn for histological study. Statistical analysis was performed with nonparametric tests and the Dunn correction for multiple comparisons. A p < 0.05 was considered significant. The direct immunofluorescence study revealed that the percentage of capillary sections thrombosed in glomerulus were significantly lesser in SL group [5 (0-28) %] compared to NC [64 (43-79) %, p = 0.01] and SB [64 (43-79), p = 0.03] groups. Alterations in platelet count and fibrinogen level occurred earlier and were significantly more pronounced in both control groups compared to SL group (p < 0.05 at 210 and 300 min). The increase in thrombin-antithrombin complexes was significantly higher in NC [754 (367-945) μg/mL; p = 0.03] and SB [463 (249-592) μg/mL; p = 0.03] groups than in SL group [176 (37-265) μg/mL]. At the end of the experiment, creatinine clearance was significantly higher in SL group [55.46 (30.07-67.85) mL/min] compared to NC group [1.52 (0.17-27.67) mL/min, p = 0.03]. In this study, we report that sodium lactate improves DIC-associated renal microvascular thrombosis and preserves GFR. These findings could at least partly explain the better fluid balance observed with sodium lactate infusion.

  1. Collisionless shock waves

    International Nuclear Information System (INIS)

    Sagdeev, R.Z.; Kennel, C.F.

    1991-01-01

    Collisionless shocks cannot occur naturally on the earth, because nearly all matter here consists of electrically neutral atoms and molecules. In space, however, high temperatures and ultraviolet radiation from hot stars decompose atoms into their constituent nuclei and electrons, producing a soup of electrically charged particles known as a plasma. Plasma physicists proposed that the collective electrical and magnetic properties of plasmas could produce interactions that take the place of collisions and permit shocks to form. In 1964 the theoretical work found its first experimental confirmation. Norman F. Ness and his colleagues at the Goddard Space Flight Center, using data collected from the iMP-1 spacecraft, detected clear signs that a collisionless shock exists where the solar wind encounters the earth's magnetic field. More recent research has demonstrated that collisionless shocks appear in a dazzling array of astronomical settings. For example, shocks have been found in the solar wind upstream (sunward) of all the planet and comets that have been visited by spacecraft. Violent flares on the sun generate shocks that propagate to the far reaches of the solar system; tremendous galactic outbursts create disruptions in the intergalactic medium that are trillions of times larger. In addition, many astrophysicists think that shocks from supernova explosions in our galaxy accelerate cosmic rays, a class of extraordinarily energetic elementary particles and atomic nuclei that rain down on the earth from all directions

  2. Pediatric Toxic Shock Syndrome

    Directory of Open Access Journals (Sweden)

    Jennifer Yee

    2017-09-01

    Full Text Available Audience: This scenario was developed to educate emergency medicine residents on the diagnosis and management of a pediatric patient with toxic shock syndrome. The case is also appropriate for teaching of medical students and advanced practice providers, as well as a review of the principles of crisis resource management, teamwork, and communication. Introduction: Toxic shock syndrome is a low-frequency, high-acuity scenario requiring timely identification and aggressive management. If patients suffering from this condition are managed incorrectly, they may progress into multi-organ dysfunction and potentially death. Toxic shock syndrome has been associated with Streptococcus and Staphylococcus aureus (Staph. Approximately half of Staph cases are associated with menstruation, which was first described in the 1970s-1980s and was associated with the use of absorbent tampons.1 Group A Streptococcus may cause complications such as necrotizing fasciitis and gangrenous myositis.2 Pediatric patients may present critically ill from toxic shock syndrome. Providers need to perform a thorough history and physical exam to discern the source of infection. Management requires aggressive care with antibiotics and IV fluids. Objectives: By the end of this simulation session, the learner will be able to: 1 Recognize toxic shock syndrome. 2 Review the importance of a thorough physical exam. 3 Discuss management of toxic shock syndrome, including supportive care and the difference in antibiotic choices for streptococcal and staphylococcal toxic shock syndrome. 4 Appropriately disposition a patient suffering from toxic shock syndrome. 5 Communicate effectively with team members and nursing staff during a resuscitation of a critically ill patient. Method: This session was conducted using high-fidelity simulation, followed by a debriefing session and lecture on toxic shock syndrome.

  3. Shocks near Jamming

    Science.gov (United States)

    Gómez, Leopoldo R.; Turner, Ari M.; van Hecke, Martin; Vitelli, Vincenzo

    2012-02-01

    Nonlinear sound is an extreme phenomenon typically observed in solids after violent explosions. But granular media are different. Right when they jam, these fragile and disordered solids exhibit a vanishing rigidity and sound speed, so that even tiny mechanical perturbations form supersonic shocks. Here, we perform simulations in which two-dimensional jammed granular packings are dynamically compressed and demonstrate that the elementary excitations are strongly nonlinear shocks, rather than ordinary phonons. We capture the full dependence of the shock speed on pressure and impact intensity by a surprisingly simple analytical model.

  4. Mechanical shock absorber

    International Nuclear Information System (INIS)

    Vrillon, Bernard.

    1973-01-01

    The mechanical shock absorber described is made of a constant thickness plate pierced with circular holes regularly distributed in such a manner that for all the directions along which the strain is applied during the shock, the same section of the substance forming the plate is achieved. The shock absorber is made in a metal standing up to extensive deformation before breaking, selected from a group comprising mild steels and austenitic stainless steels. This apparatus is used for handling pots of fast neutron reactor fuel elements [fr

  5. Shock formation of HCO+

    International Nuclear Information System (INIS)

    Elitzur, M.

    1983-01-01

    It is shown that shocks propagating in dense molecular regions will lead to a decrease in HCO + relative abundance, in agreement with previous results by Iglesias and Silk. The shock enhancement of HCO + detected in the supernova remnant IC 443 by Dickenson et al. is due to enhanced ionization in the shocked material. This is the result of the material penetrating the remnant cavity where it becomes exposed to the trapped cosmic rays. A similar enhancement appears to have been detected by Wootten in W28 and is explained by the same model

  6. Computed tomography of lethal medline granuloma

    International Nuclear Information System (INIS)

    Lee, Ho Suk; Kim, Tae Ho; Suh, Kyung Jin; Kim, Tae Hun; Kim, Yong Joo; Kang, Duk Sik

    1991-01-01

    In order to clarify the CT findings of lethal midline granuloma (LMG) diagnosed clinically or histopathologically, the authors retrospectively analyzed 12 patients who were seen at Kyungpook National University Hospital from February 1985 to August 1989. CT showed nasal mucosal thickening and / or soft tissue mass (9 case), spreading of the lesions along the facial subcutaneous fat plane (8 cases), invasion into the paranasal sinuses (5 cases), bone destruction (5 cases), nasopharyngeal mass lesion (2 cases), and extension of the lesion into the infratemporal fossa (1 case). In spite of the fact that CT does not make definitive diagnosis of LMG, it permits evaluation of the extent of the lesion, detection of the combined lesion, differential diagnosis, and close monitoring of its evolution under treatment

  7. Gluconeogenesis in lethally X-irradiated rats

    International Nuclear Information System (INIS)

    Paulikova, E.; Ahlers, I.; Praslicka, M.

    1983-01-01

    The in vivo incorporation of U- 14 C-alanine into blood glucose and liver glycogen was measured in rats irradiated with a single whole body lethal dose of X-rays. Changes in gluconeogenic enzyme activities were studied in the liver. Increased incorporation of 14 C-alanine into blood glucose and liver glycogen were found after irradiation. Liver phosphoenolpyruvate carboxykinase and glycogenic activity underwent almost parallel changes and were significantly elevated from the 6th to the 48th hour, with resultant accumulation of glycogen. Glucose-6-phosphatase activity was depressed and there was a negative correlation between it and liver glycogen concentration. Maximum fructose-1,6-diphosphatase activity was found at 48 hours. The results show that glycogen accumulation in the liver and the raised blood glucose level in X-irradiated rats are based on raised gluconeogenesis. (author)

  8. Gluconeogenesis in lethally X-irradiated rats

    Energy Technology Data Exchange (ETDEWEB)

    Paulikova, E.; Ahlers, I.; Praslicka, M. (Univerzita P.J. Safarika, Kosice (Czechoslovakia). Katedra Vseobecnej Biologie)

    1983-02-01

    The in vivo incorporation of U-/sup 14/C-alanine into blood glucose and liver glycogen was measured in rats irradiated with a single whole body lethal dose of X-rays. Changes in gluconeogenic enzyme activities were studied in the liver. Increased incorporation of /sup 14/C-alanine into blood glucose and liver glycogen were found after irradiation. Liver phosphoenolpyruvate carboxykinase and glycogenic activity underwent almost parallel changes and were significantly elevated from the 6th to the 48th hour, with resultant accumulation of glycogen. Glucose-6-phosphatase activity was depressed and there was a negative correlation between it and liver glycogen concentration. Maximum fructose-1,6-diphosphatase activity was found at 48 hours. The results show that glycogen accumulation in the liver and the raised blood glucose level in X-irradiated rats are based on raised gluconeogenesis.

  9. Ants defend aphids against lethal disease

    Science.gov (United States)

    Nielsen, Charlotte; Agrawal, Anurag A.; Hajek, Ann E.

    2010-01-01

    Social insects defend their own colonies and some species also protect their mutualist partners. In mutualisms with aphids, ants typically feed on honeydew produced by aphids and, in turn guard and shelter aphid colonies from insect natural enemies. Here we report that Formica podzolica ants tending milkweed aphids, Aphis asclepiadis, protect aphid colonies from lethal fungal infections caused by an obligate aphid pathogen, Pandora neoaphidis. In field experiments, bodies of fungal-killed aphids were quickly removed from ant-tended aphid colonies. Ant workers were also able to detect infective conidia on the cuticle of living aphids and responded by either removing or grooming these aphids. Our results extend the long-standing view of ants as mutualists and protectors of aphids by demonstrating focused sanitizing and quarantining behaviour that may lead to reduced disease transmission in aphid colonies. PMID:19923138

  10. Lethal photosensitization of biofilm-grown bacteria

    Science.gov (United States)

    Wilson, Michael

    1997-12-01

    Antibacterial agents are increasingly being used for the prophylaxis and treatment of oral diseases. As these agents can be rendered ineffective by resistance development in the target organisms there is a need to develop alternative antimicrobial approaches. Light-activated antimicrobial agents release singlet oxygen and free radicals which can kill adjacent bacteria and a wide range of cariogenic and periodontopathogenic bacteria has been shown to be susceptible to such agents. In the oral cavity these organisms are present as biofilms (dental plaques) which are less susceptible to traditional antimicrobial agents than bacterial suspensions. The results of these studies have shown that biofilm-grown oral bacteria are also susceptible to lethal photosensitization although the light energy doses required are grater than those needed to kill the organisms when they are grown as aqueous suspensions.

  11. Shock Isolation Elements Testing for High Input Loadings. Volume II. Foam Shock Isolation Elements.

    Science.gov (United States)

    SHOCK ABSORBERS ), (*GUIDED MISSILE SILOS, SHOCK ABSORBERS ), (*EXPANDED PLASTICS, (*SHOCK(MECHANICS), REDUCTION), TEST METHODS, SHOCK WAVES, STRAIN(MECHANICS), LOADS(FORCES), MATHEMATICAL MODELS, NUCLEAR EXPLOSIONS, HARDENING.

  12. Tityus serrulatus venom--A lethal cocktail.

    Science.gov (United States)

    Pucca, Manuela Berto; Cerni, Felipe Augusto; Pinheiro Junior, Ernesto Lopes; Bordon, Karla de Castro Figueiredo; Amorim, Fernanda Gobbi; Cordeiro, Francielle Almeida; Longhim, Heloisa Tavoni; Cremonez, Caroline Marroni; Oliveira, Guilherme Honda; Arantes, Eliane Candiani

    2015-12-15

    Tityus serrulatus (Ts) is the main scorpion species of medical importance in Brazil. Ts venom is composed of several compounds such as mucus, inorganic salts, lipids, amines, nucleotides, enzymes, kallikrein inhibitor, natriuretic peptide, proteins with high molecular mass, peptides, free amino acids and neurotoxins. Neurotoxins are considered the most responsible for the envenoming syndrome due to their pharmacological action on ion channels such as voltage-gated sodium (Nav) and potassium (Kv) channels. The major goal of this review is to present important advances in Ts envenoming research, correlating both the crude Ts venom and isolated toxins with alterations observed in all human systems. The most remarkable event lies in the Ts induced massive releasing of neurotransmitters influencing, directly or indirectly, the entire body. Ts venom proved to extremely affect nervous and muscular systems, to modulate the immune system, to induce cardiac disorders, to cause pulmonary edema, to decrease urinary flow and to alter endocrine, exocrine, reproductive, integumentary, skeletal and digestive functions. Therefore, Ts venom possesses toxins affecting all anatomic systems, making it a lethal cocktail. However, its low lethality may be due to the low venom mass injected, to the different venom compositions, the body characteristics and health conditions of the victim and the local of Ts sting. Furthermore, we also described the different treatments employed during envenoming cases. In particular, throughout the review, an effort will be made to provide information from an extensive documented studies concerning Ts venom in vitro, in animals and in humans (a total of 151 references). Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Counseling For Future Shock

    Science.gov (United States)

    Morgan, Lewis B.

    1974-01-01

    In this article the author looks at some of the searing prophecies made by Alvin Toffler in his book Future Shock and relates them to the world of the professional counselor and the clientele the counselor attempts to serve. (Author)

  14. Life shocks and homelessness.

    Science.gov (United States)

    Curtis, Marah A; Corman, Hope; Noonan, Kelly; Reichman, Nancy E

    2013-12-01

    We exploited an exogenous health shock-namely, the birth of a child with a severe health condition-to investigate the effect of a life shock on homelessness in large cities in the United States as well as the interactive effects of the shock with housing market characteristics. We considered a traditional measure of homelessness, two measures of housing instability thought to be precursors to homelessness, and a combined measure that approximates the broadened conceptualization of homelessness under the 2009 Homeless Emergency Assistance and Rapid Transition to Housing Act (2010). We found that the shock substantially increases the likelihood of family homelessness, particularly in cities with high housing costs. The findings are consistent with the economic theory of homelessness, which posits that homelessness results from a conjunction of adverse circumstances in which housing markets and individual characteristics collide.

  15. Unlimited Relativistic Shock Surfing Acceleration

    International Nuclear Information System (INIS)

    Ucer, D.; Shapiro, V. D.

    2001-01-01

    Nonrelativistic shock surfing acceleration at quasiperpendicular shocks is usually considered to be a preacceleration mechanism for slow pickup ions to initiate diffusive shock acceleration. In shock surfing, the particle accelerates along the shock front under the action of the convective electric field of the plasma flow. However, the particle also gains kinetic energy normal to the shock and eventually escapes downstream. We consider the case when ions are accelerated to relativistic velocities. In this case, the ions are likely to be trapped for infinitely long times, because the energy of bounce oscillations tends to decrease during acceleration. This suggests the possibility of unlimited acceleration by shock surfing

  16. Technology shocks matter

    OpenAIRE

    Jonas D. M. Fisher

    2002-01-01

    This paper uses the neoclassical growth model to identify the effects of technological change on the US business cycle. In the model there are two sources of technological change: neutral, which effects the production of all goods homogeneously, and investment-specific. Investment-specific shocks are the unique source of the secular trend in the real price of investment goods, while shocks to both kinds of technology are the only factors which affect labor productivity in the long run. Consis...

  17. The Heliospheric Termination Shock

    Science.gov (United States)

    Jokipii, J. R.

    2013-06-01

    The heliospheric termination shock is a vast, spheroidal shock wave marking the transition from the supersonic solar wind to the slower flow in the heliosheath, in response to the pressure of the interstellar medium. It is one of the most-important boundaries in the outer heliosphere. It affects energetic particles strongly and for this reason is a significant factor in the effects of the Sun on Galactic cosmic rays. This paper summarizes the general properties and overall large-scale structure and motions of the termination shock. Observations over the past several years, both in situ and remote, have dramatically revised our understanding of the shock. The consensus now is that the shock is quite blunt, is with the front, blunt side canted at an angle to the flow direction of the local interstellar plasma relative to the Sun, and is dynamical and turbulent. Much of this new understanding has come from remote observations of energetic charged particles interacting with the shock, radio waves and radiation backscattered from interstellar neutral atoms. The observations and the implications are discussed.

  18. Chronic exposure of corals to fine sediments: lethal and sub-lethal impacts.

    Directory of Open Access Journals (Sweden)

    Florita Flores

    Full Text Available Understanding the sedimentation and turbidity thresholds for corals is critical in assessing the potential impacts of dredging projects in tropical marine systems. In this study, we exposed two species of coral sampled from offshore locations to six levels of total suspended solids (TSS for 16 weeks in the laboratory, including a 4 week recovery period. Dose-response relationships were developed to quantify the lethal and sub-lethal thresholds of sedimentation and turbidity for the corals. The sediment treatments affected the horizontal foliaceous species (Montipora aequituberculata more than the upright branching species (Acropora millepora. The lowest sediment treatments that caused full colony mortality were 30 mg l(-1 TSS (25 mg cm(-2 day(-1 for M. aequituberculata and 100 mg l(-1 TSS (83 mg cm(-2 day(-1 for A. millepora after 12 weeks. Coral mortality generally took longer than 4 weeks and was closely related to sediment accumulation on the surface of the corals. While measurements of damage to photosystem II in the symbionts and reductions in lipid content and growth indicated sub-lethal responses in surviving corals, the most reliable predictor of coral mortality in this experiment was long-term sediment accumulation on coral tissue.

  19. Chronic Exposure of Corals to Fine Sediments: Lethal and Sub-Lethal Impacts

    Science.gov (United States)

    Flores, Florita; Hoogenboom, Mia O.; Smith, Luke D.; Cooper, Timothy F.; Abrego, David; Negri, Andrew P.

    2012-01-01

    Understanding the sedimentation and turbidity thresholds for corals is critical in assessing the potential impacts of dredging projects in tropical marine systems. In this study, we exposed two species of coral sampled from offshore locations to six levels of total suspended solids (TSS) for 16 weeks in the laboratory, including a 4 week recovery period. Dose-response relationships were developed to quantify the lethal and sub-lethal thresholds of sedimentation and turbidity for the corals. The sediment treatments affected the horizontal foliaceous species (Montipora aequituberculata) more than the upright branching species (Acropora millepora). The lowest sediment treatments that caused full colony mortality were 30 mg l−1 TSS (25 mg cm−2 day−1) for M. aequituberculata and 100 mg l−1 TSS (83 mg cm−2 day−1) for A. millepora after 12 weeks. Coral mortality generally took longer than 4 weeks and was closely related to sediment accumulation on the surface of the corals. While measurements of damage to photosystem II in the symbionts and reductions in lipid content and growth indicated sub-lethal responses in surviving corals, the most reliable predictor of coral mortality in this experiment was long-term sediment accumulation on coral tissue. PMID:22662225

  20. Repair of potentially lethal damage by introduction of T4 DNA ligase in eucaryotic cells

    International Nuclear Information System (INIS)

    Durante, M.; Grossi, G.F.; Napolitano, M.; Gialanella, G.

    1991-01-01

    The bacterial enzyme PvuII, which generates blunt-ended DNA double-strand breaks, and T4 DNA ligase, which seals adjacent DNA fragments in coupling to ATP cleavage, were introduced in mouse C3H10T1/2 fibroblasts using osmolytic shock of pinocytic vesicles. Cells were then assayed for their clonogenic ability. In agreement with previous studies by others, the authors found that PvuII restriction endonuclease simulates ionizing radiation effects by causing a dose-dependent loss of reproductive capacity. They show that concomitant treatment with DNA ligase considerably increases cell survival. Survival curves were shown to be dependent on ligase enzyme dose and on ATP concentration in the hypertonic medium. They conclude that T4 DNA ligase is able to repair some potentially lethal damage produced by restriction endonucleases in eucaryotic cells. (author)

  1. Forkhead Box M1 Is Regulated by Heat Shock Factor 1 and Promotes Glioma Cells Survival under Heat Shock Stress*

    Science.gov (United States)

    Dai, Bingbing; Gong, Aihua; Jing, Zhitao; Aldape, Kenneth D.; Kang, Shin-Hyuk; Sawaya, Raymond; Huang, Suyun

    2013-01-01

    The forkhead box M1 (FoxM1) is a key transcription factor regulating multiple aspects of cell biology. Prior studies have shown that FoxM1 is overexpressed in a variety of human tumors, including brain tumor, and plays a critical role in cancer development and progression. In this study we found that FoxM1 was up-regulated by heat shock factor 1 (HSF1) under heat shock stress condition in multiple cell lines. Knockdown of HSF1 with HSF1 siRNA or inhibition of HSF1 with a HSF1 inhibitor abrogated heat shock-induced expression of FoxM1. Genetic deletion of HSF1 in mouse embryo fibroblast cells also abolished heat shock stress-induced FoxM1 expression. Moreover, we showed that HSF1 directly bound to FoxM1 promoter and increased FoxM1 promoter activity. Furthermore, we demonstrated that FoxM1 was required for the G2-M phase progression through regulating Cdc2, Cdc20, and Cdc25B under a mild heat shock stress but enhanced cell survival under lethal heat shock stress condition. Finally, in human glioblastoma specimens, FoxM1 overexpression correlated with elevated HSF1 expression. Our results indicate that FoxM1 is regulated by HSF1 and is critical for HSF1-mediated heat shock response. We demonstrated a novel mechanism of stress resistance controlled by HSF1 and a new HSF-FoxM1 connection that mediates cellular thermotolerance. PMID:23192351

  2. Lethal and sub-lethal effects of five pesticides used in rice farming on the earthworm Eisenia fetida

    NARCIS (Netherlands)

    Rico, Andreu; Sabater, Consuelo; Castillo, María Ángeles

    2016-01-01

    The toxicity of five pesticides typically used in rice farming (trichlorfon, dimethoate, carbendazim, tebuconazole and prochloraz) was evaluated on different lethal and sub-lethal endpoints of the earthworm Eisenia fetida. The evaluated endpoints included: avoidance behaviour after an exposure

  3. Heat shock protein 72: release and biological significance during exercise.

    Science.gov (United States)

    Whitham, Martin; Fortes, Matthew Benjamin

    2008-01-01

    The cumulative stressors of exercise manifest themselves at a cellular level by threatening the protein homeostasis of the cell. In these conditions, Heat Shock Proteins (HSP) are synthesised to chaperone mis-folded and denatured proteins. As such, the intracellular HSP response is thought to aid cell survival in the face of otherwise lethal cellular stress. Recently, the inducible isoform of the 70 Kda heat shock protein family, Hsp72 has been detected in the extracellular environment. Furthermore, the release of this protein into the circulation has been shown to occur in response to a range of exercise bouts. The present review summarises the current research on the exercise Hsp72 response, the possible mediators and mechanisms of extracellular (e)Hsp72 release, and the possible biological significance of this systemic response. In particular, the possible role of eHsp72 in the modulation of immunity during exercise is discussed.

  4. Lethal endomyocarditis caused by chronic "Krokodil" intoxication.

    Science.gov (United States)

    Sorrentino, Antonella; Trotta, Silvia; Colucci, Anna Pia; Aventaggiato, Lucia; Marzullo, Andrea; Solarino, Biagio

    2018-03-19

    "Krokodil" is a home-made opioid drug obtained by synthesizing desomorphine from codeine and combining it with other low-cost additives. Initially introduced in the former Soviet countries, it was then imported to Western Europe as a heroin substitute. To our knowledge, this is the first report of an Italian case of lethal krokodil abuse, that occurred in a 39-year-old man, who died suddenly after transportation to the Emergency Department (ED) for hyperthermia associated with sweating, dyspnoea and tachycardia. Post-mortem examination revealed extensive necrotic ulcerative lesions on the forearms, and autopsy showed a hypertrophic heart with ample endocardial vegetation on the aortic valve and patency of the foramen ovale. Histopathological examination of the heart showed ulcero-vegetative lesions of the aortic valve with an abscess on the annulus and extension to the periaortic adipose tissue, as well as diffuse myocardial interstitial inflammatory neutrophilic infiltrates. Toxicological analysis demonstrated a desomorphine metabolite in urine. On the basis of all these findings the cause of death was ruled to be congestive heart failure caused by endocarditis and myocarditis, correlated with chronic abuse of krokodil.

  5. Tumor clone dynamics in lethal prostate cancer.

    Science.gov (United States)

    Carreira, Suzanne; Romanel, Alessandro; Goodall, Jane; Grist, Emily; Ferraldeschi, Roberta; Miranda, Susana; Prandi, Davide; Lorente, David; Frenel, Jean-Sebastien; Pezaro, Carmel; Omlin, Aurelius; Rodrigues, Daniel Nava; Flohr, Penelope; Tunariu, Nina; S de Bono, Johann; Demichelis, Francesca; Attard, Gerhardt

    2014-09-17

    It is unclear whether a single clone metastasizes and remains dominant over the course of lethal prostate cancer. We describe the clonal architectural heterogeneity at different stages of disease progression by sequencing serial plasma and tumor samples from 16 ERG-positive patients. By characterizing the clonality of commonly occurring deletions at 21q22, 8p21, and 10q23, we identified multiple independent clones in metastatic disease that are differentially represented in tissue and circulation. To exemplify the clinical utility of our studies, we then showed a temporal association between clinical progression and emergence of androgen receptor (AR) mutations activated by glucocorticoids in about 20% of patients progressing on abiraterone and prednisolone or dexamethasone. Resistant clones showed a complex dynamic with temporal and spatial heterogeneity, suggesting distinct mechanisms of resistance at different sites that emerged and regressed depending on treatment selection pressure. This introduces a management paradigm requiring sequential monitoring of advanced prostate cancer patients with plasma and tumor biopsies to ensure early discontinuation of agents when they become potential disease drivers. Copyright © 2014, American Association for the Advancement of Science.

  6. Human cooperation by lethal group competition.

    Science.gov (United States)

    Egas, Martijn; Kats, Ralph; van der Sar, Xander; Reuben, Ernesto; Sabelis, Maurice W

    2013-01-01

    Why humans are prone to cooperate puzzles biologists, psychologists and economists alike. Between-group conflict has been hypothesized to drive within-group cooperation. However, such conflicts did not have lasting effects in laboratory experiments, because they were about luxury goods, not needed for survival ("looting"). Here, we find within-group cooperation to last when between-group conflict is implemented as "all-out war" (eliminating the weakest groups). Human subjects invested in helping group members to avoid having the lowest collective pay-off, whereas they failed to cooperate in control treatments with random group elimination or with no subdivision in groups. When the game was repeated, experience was found to promote helping. Thus, not within-group interactions alone, not random group elimination, but pay-off-dependent group elimination was found to drive within-group cooperation in our experiment. We suggest that some forms of human cooperation are maintained by multi-level selection: reciprocity within groups and lethal competition among groups acting together.

  7. Shocks in fragile matter

    Science.gov (United States)

    Vitelli, Vincenzo

    2012-02-01

    Non-linear sound is an extreme phenomenon typically observed in solids after violent explosions. But granular media are different. Right when they unjam, these fragile and disordered solids exhibit vanishing elastic moduli and sound speed, so that even tiny mechanical perturbations form supersonic shocks. Here, we perform simulations in which two-dimensional jammed granular packings are continuously compressed, and demonstrate that the resulting excitations are strongly nonlinear shocks, rather than linear waves. We capture the full dependence of the shock speed on pressure and compression speed by a surprisingly simple analytical model. We also treat shear shocks within a simplified viscoelastic model of nearly-isostatic random networks comprised of harmonic springs. In this case, anharmonicity does not originate locally from nonlinear interactions between particles, as in granular media; instead, it emerges from the global architecture of the network. As a result, the diverging width of the shear shocks bears a nonlinear signature of the diverging isostatic length associated with the loss of rigidity in these floppy networks.

  8. Physics of Collisionless Shocks Space Plasma Shock Waves

    CERN Document Server

    Balogh, André

    2013-01-01

    The present book provides a contemporary systematic treatment of shock waves in high-temperature collisionless plasmas as are encountered in near Earth space and in Astrophysics. It consists of two parts. Part I develops the complete theory of shocks in dilute hot plasmas under the assumption of absence of collisions among the charged particles when the interaction is mediated solely by the self-consistent electromagnetic fields. Such shocks are naturally magnetised implying that the magnetic field plays an important role in their evolution and dynamics. This part treats both subcritical shocks, which dissipate flow energy by generating anomalous resistance or viscosity, and supercritical shocks. The main emphasis is, however, on super-critical shocks where the anomalous dissipation is insufficient to retard the upstream flow. These shocks, depending on the direction of the upstream magnetic field, are distinguished as quasi-perpendicular and quasi-parallel shocks which exhibit different behaviours, reflecti...

  9. Life Shocks and Homelessness

    Science.gov (United States)

    Corman, Hope; Noonan, Kelly; Reichman, Nancy E.

    2014-01-01

    We exploited an exogenous health shock—namely, the birth of a child with a severe health condition—to investigate the effect of a life shock on homelessness in large cities in the United States as well as the interactive effects of the shock with housing market characteristics. We considered a traditional measure of homelessness, two measures of housing instability thought to be precursors to homelessness, and a combined measure that approximates the broadened conceptualization of homelessness under the 2009 Homeless Emergency Assistance and Rapid Transition to Housing Act (2010). We found that the shock substantially increases the likelihood of family homelessness, particularly in cities with high housing costs. The findings are consistent with the economic theory of homelessness, which posits that homelessness results from a conjunction of adverse circumstances in which housing markets and individual characteristics collide. PMID:23868747

  10. Health Shocks and Retirement:

    DEFF Research Database (Denmark)

    Datta Gupta, Nabanita; Larsen, Mona

    We investigate the effect of an acute health shock on retirement among elderly male workers in Denmark, 1991-1999, and in particular whether various welfare state programs and institutions impinge on the retirement effect. The results show that an acute health event increases the retirement chances...... significant. For the most part, the retirement effect following a health shock seems to be immune to the availability of a multitude of government programs for older workers in Denmark....... benefits in Denmark nor by the promotion of corporate social responsibility initiatives since the mid-1990s. In the late 1990s, however, the retirement rate following a health shock is reduced to 3% with the introduction of the subsidized employment program (fleksjob) but this effect is not strongly...

  11. The Shock Routine

    DEFF Research Database (Denmark)

    van Hooren, Franca; Kaasch, Alexandra; Starke, Peter

    2014-01-01

    in Australia, Belgium, the Netherlands and Sweden over the course of four global economic shocks, we ask whether the notion of critical junctures is useful in understanding the nature of change triggered by crisis. The main empirical finding is that fundamental change in the aftermath of an exogenous shock...... is the exception rather than the rule. Instead, incremental ‘crisis routines’ based on existing policy instruments are overwhelmingly used to deal with economic hardship. We discuss these findings in the light of the psychological ‘threat-rigidity’ effect and reflect on their consequences for theories...

  12. Non-lethal Clostridium sordellii bacteraemia in an immunocompromised patient with pleomorphic sarcoma.

    Science.gov (United States)

    Bonnecaze, Alex K; Stephens, Sarah Ellen Elza; Miller, Peter John

    2016-08-03

    Clostridium sordellii is a spore-forming anaerobic Gram-positive rod that has rarely been reported to cause disease in humans. Resultant mortality from infection is estimated at nearly 70% and is most often correlated with gynaecological procedures, intravenous drug abuse or trauma. C. sordellii infection often presents similarly to toxic shock syndrome (TSS); notable features of infection include refractory hypotension, haemoconcentration and marked leucocytosis. Although clinically similar to TSS, a notable difference is C. sordellii infections rarely involve fever. The organism's major toxins include haemorrhagic (TcsH) and lethal factor (TcsL), which function to disrupt cytoskeletal integrity. Current literature suggests treating C. sordelli infection with a broad-spectrum penicillin, metronidazole and clindamycin. We present a case of C. sordellii bacteraemia and septic shock in an immunocompromised patient who was recently diagnosed with pleomorphic gluteal sarcoma. Despite presenting in critical condition, the patient improved after aggressive hemodynamic resuscitation, source control and intravenous antibiotic therapy. 2016 BMJ Publishing Group Ltd.

  13. Shock absorber in Ignalina NPP

    International Nuclear Information System (INIS)

    Bulavas, A.; Muralis, J.

    1996-09-01

    Theoretical calculation and experimental analysis of models of shock absorber in Ignalina NPP is presented. The results obtained from the investigation with model of shock absorber coincide with the theoretical calculation. (author). 2 figs., 3 refs

  14. Shock Response of Boron Carbide

    National Research Council Canada - National Science Library

    Dandekar, D. P. (Dattatraya Purushottam)

    2001-01-01

    .... The present work was undertaken to determine tensile/spall strength of boron carbide under plane shock wave loading and to analyze all available shock compression data on boron carbide materials...

  15. Fascinating World of Shock Waves

    Indian Academy of Sciences (India)

    Srimath

    travelling at supersonic speeds (more than the sound speed at ... actual earth- quake, travel at supersonic speeds. .... The time scale of the shock wave is also important ..... real lithotripsy where a shock wave is used shatter the kidney stones!

  16. INTERFERENCE OF UNIDIRECTIONAL SHOCK WAVES

    Directory of Open Access Journals (Sweden)

    P. V. Bulat

    2015-05-01

    Full Text Available Subject of study.We consider interference of unidirectional shock waves or, as they are called, catching up shock waves. The scope of work is to give a classification of the shock-wave structures that arise in this type of interaction of shock waves, and the area of their existence. Intersection of unidirectional shock waves results in arising of a shock-wave structure at the intersection point, which contains the main shock wave, tangential discontinuity and one more reflected gas-dynamic discontinuity of unknown beforehand type. The problem of determining the type of reflected discontinuity is the main problem that one has to solve in the study of catching shock waves interference. Main results.The paper presents the pictures of shock-wave structures arising at the interaction of catching up shock waves. The areas with a regular and irregular unidirectional interaction of shocks are described. Characteristic shock-wave structures are of greatest interest, where reflected gas-dynamic discontinuity degenerates into discontinuous characteristics. Such structures have a number of extreme properties. We have found the areas of existence for such shock-wave structures. There are also areas in which the steady-state solution is not available. The latter has determined revival of interest for the theoretical study of the problem, because the facts of sudden shock-wave structure destruction inside the air intake of supersonic aircrafts at high Mach numbers have been discovered. Practical significance.The theory of interference for unidirectional shock waves and design procedure are usable in the design of supersonic air intakes. It is also relevant for application possibility investigation of catching up oblique shock waves to create overcompressed detonation in perspective detonation air-jet and rocket engines.

  17. A new type of lethal short-limbed dwarfism

    International Nuclear Information System (INIS)

    Nairn, E.R.; Chapman, S.

    1989-01-01

    Details are presented of a most unusual osteo-chondrodysplasia which presents with lethal neonatal short-limbed dwarfism, defective ossification and nodular calcification with cartilage. The features resemble one case previously described in the literature. (orig.)

  18. Back to the future: revisiting HIV-1 lethal mutagenesis

    Science.gov (United States)

    Dapp, Michael J.; Patterson, Steven E.; Mansky, Louis M.

    2012-01-01

    The concept of eliminating HIV-1 infectivity by elevating the viral mutation rate was first proposed over a decade ago, even though the general concept had been conceived earlier for RNA viruses. Lethal mutagenesis was originally viewed as a novel chemotherapeutic approach for treating HIV-1 infection in which use of a viral mutagen would over multiple rounds of replication lead to the lethal accumulation of mutations, rendering the virus population non infectious – known as the slow mutation accumulation model. There have been limitations in obtaining good efficacy data with drug leads, leaving some doubt into clinical translation. More recent studies of the APOBEC3 proteins as well as new progress in the use of nucleoside analogs for inducing lethal mutagenesis have helped to refocus attention on rapid induction of HIV-1 lethal mutagenesis in a single or limited number of replication cycles leading to a rapid mutation accumulation model. PMID:23195922

  19. New type of lethal short-limbed dwarfism

    Energy Technology Data Exchange (ETDEWEB)

    Nairn, E.R.; Chapman, S.

    1989-05-01

    Details are presented of a most unusual osteo-chondrodysplasia which presents with lethal neonatal short-limbed dwarfism, defective ossification and nodular calcification with cartilage. The features resemble one case previously described in the literature.

  20. Shock tube Multiphase Experiments

    Science.gov (United States)

    Middlebrooks, John; Allen, Roy; Paudel, Manoj; Young, Calvin; Musick, Ben; McFarland, Jacob

    2017-11-01

    Shock driven multiphase instabilities (SDMI) are unique physical phenomena that have far-reaching practical applications in engineering and science. The instability is present in high energy explosions, scramjet combustors, and supernovae events. The SDMI arises when a multiphase interface is impulsively accelerated by the passage of a shockwave. It is similar in development to the Richtmyer-Meshkov (RM) instability however, particle-to-gas coupling is the driving mechanism of the SDMI. As particle effects such as lag and phase change become more prominent, the SDMI's development begins to significantly deviate from the RM instability. We have developed an experiment for studying the SDMI in our shock tube facility. In our experiments, a multiphase interface is created using a laminar jet and flowed into the shock tube where it is accelerated by the passage of a planar shockwave. The interface development is captured using CCD cameras synchronized with planar laser illumination. This talk will give an overview of new experiments conducted to examine the development of a shocked cylindrical multiphase interface. The effects of Atwood number, particle size, and a second acceleration (reshock) of the interface will be discussed.

  1. Teleconnected food supply shocks

    Science.gov (United States)

    Bren d'Amour, Christopher; Wenz, Leonie; Kalkuhl, Matthias; Steckel, Jan Christoph; Creutzig, Felix

    2016-03-01

    The 2008-2010 food crisis might have been a harbinger of fundamental climate-induced food crises with geopolitical implications. Heat-wave-induced yield losses in Russia and resulting export restrictions led to increases in market prices for wheat across the Middle East, likely contributing to the Arab Spring. With ongoing climate change, temperatures and temperature variability will rise, leading to higher uncertainty in yields for major nutritional crops. Here we investigate which countries are most vulnerable to teleconnected supply-shocks, i.e. where diets strongly rely on the import of wheat, maize, or rice, and where a large share of the population is living in poverty. We find that the Middle East is most sensitive to teleconnected supply shocks in wheat, Central America to supply shocks in maize, and Western Africa to supply shocks in rice. Weighing with poverty levels, Sub-Saharan Africa is most affected. Altogether, a simultaneous 10% reduction in exports of wheat, rice, and maize would reduce caloric intake of 55 million people living in poverty by about 5%. Export bans in major producing regions would put up to 200 million people below the poverty line at risk, 90% of which live in Sub-Saharan Africa. Our results suggest that a region-specific combination of national increases in agricultural productivity and diversification of trade partners and diets can effectively decrease future food security risks.

  2. STEREO interplanetary shocks and foreshocks

    International Nuclear Information System (INIS)

    Blanco-Cano, X.; Kajdič, P.; Aguilar-Rodríguez, E.; Russell, C. T.; Jian, L. K.; Luhmann, J. G.

    2013-01-01

    We use STEREO data to study shocks driven by stream interactions and the waves associated with them. During the years of the extended solar minimum 2007-2010, stream interaction shocks have Mach numbers between 1.1-3.8 and θ Bn ∼20-86°. We find a variety of waves, including whistlers and low frequency fluctuations. Upstream whistler waves may be generated at the shock and upstream ultra low frequency (ULF) waves can be driven locally by ion instabilities. The downstream wave spectra can be formed by both, locally generated perturbations, and shock transmitted waves. We find that many quasiperpendicular shocks can be accompanied by ULF wave and ion foreshocks, which is in contrast to Earth's bow shock. Fluctuations downstream of quasi-parallel shocks tend to have larger amplitudes than waves downstream of quasi-perpendicular shocks. Proton foreshocks of shocks driven by stream interactions have extensions dr ≤0.05 AU. This is smaller than foreshock extensions for ICME driven shocks. The difference in foreshock extensions is related to the fact that ICME driven shocks are formed closer to the Sun and therefore begin to accelerate particles very early in their existence, while stream interaction shocks form at ∼1 AU and have been producing suprathermal particles for a shorter time.

  3. STEREO interplanetary shocks and foreshocks

    Energy Technology Data Exchange (ETDEWEB)

    Blanco-Cano, X. [Instituto de Geofisica, UNAM, CU, Coyoacan 04510 DF (Mexico); Kajdic, P. [IRAP-University of Toulouse, CNRS, Toulouse (France); Aguilar-Rodriguez, E. [Instituto de Geofisica, UNAM, Morelia (Mexico); Russell, C. T. [ESS and IGPP, University of California, Los Angeles, 603 Charles Young Drive, Los Angeles, CA 90095 (United States); Jian, L. K. [NASA Goddard Space Flight Center, Greenbelt, MD and University of Maryland, College Park, MD (United States); Luhmann, J. G. [SSL, University of California Berkeley (United States)

    2013-06-13

    We use STEREO data to study shocks driven by stream interactions and the waves associated with them. During the years of the extended solar minimum 2007-2010, stream interaction shocks have Mach numbers between 1.1-3.8 and {theta}{sub Bn}{approx}20-86 Degree-Sign . We find a variety of waves, including whistlers and low frequency fluctuations. Upstream whistler waves may be generated at the shock and upstream ultra low frequency (ULF) waves can be driven locally by ion instabilities. The downstream wave spectra can be formed by both, locally generated perturbations, and shock transmitted waves. We find that many quasiperpendicular shocks can be accompanied by ULF wave and ion foreshocks, which is in contrast to Earth's bow shock. Fluctuations downstream of quasi-parallel shocks tend to have larger amplitudes than waves downstream of quasi-perpendicular shocks. Proton foreshocks of shocks driven by stream interactions have extensions dr {<=}0.05 AU. This is smaller than foreshock extensions for ICME driven shocks. The difference in foreshock extensions is related to the fact that ICME driven shocks are formed closer to the Sun and therefore begin to accelerate particles very early in their existence, while stream interaction shocks form at {approx}1 AU and have been producing suprathermal particles for a shorter time.

  4. Perinatal-lethal Gaucher disease presenting as hydrops fetalis.

    Science.gov (United States)

    BenHamida, Emira; Ayadi, Imene; Ouertani, Ines; Chammem, Maroua; Bezzine, Ahlem; BenTmime, Riadh; Attia, Leila; Mrad, Ridha; Marrakchi, Zahra

    2015-01-01

    Perinatal-lethal Gaucher disease is very rare and is considered a variant of type 2 Gaucher disease that occurs in the neonatal period. The most distinct features of perinatal-lethal Gaucher disease are non-immune hydrops fetalis. Less common signs of the disease are hepatosplenomegaly, ichthyosis and arthrogryposis. We report a case of Gaucher's disease (type 2) diagnosed in a newborn who presented with Hydrops Fetalis.

  5. Conflict Without Casualties: Non-Lethal Weapons in Irregular Warfare

    Science.gov (United States)

    2007-09-01

    the body,” and the Geneva Protocol of 1925, bans the use of chemical and biological weapons .11 On 8 April 1975, President Ford issued Executive...E Funding – PE 63851M) (accessed 15 December 2006). The American Journal of Bioethics . “Medical Ethics and Non-Lethal Weapons .” Bioethics.net...CASUALTIES: NON-LETHAL WEAPONS IN IRREGULAR WARFARE by Richard L. Scott September 2007 Thesis Advisor: Robert McNab Second Reader

  6. Non-Lethal Weapons: Opportunities for R&D

    Science.gov (United States)

    2004-12-01

    during the Vietnam War. US; emulsifying agents are used in food processing, drilling fluids, cosmetics , pharmaceuticals, heavy- duty cleaners, textile...conducted in a professional manner, with no threat to public safety or the environment. 11 References [1] Fenton , G., (2001). NLW Technology Taxonomy...W.A., Mason, R.L., Collins, K.R., (2000). Non-Lethal Applicants of Slippery Substances. NDIA Non-Lethal Defense IV. [24] Fenton , G., (2000). Overview

  7. Lethal synergy involving bicyclomycin: an approach for reviving old antibiotics.

    Science.gov (United States)

    Malik, Muhammad; Li, Liping; Zhao, Xilin; Kerns, Robert J; Berger, James M; Drlica, Karl

    2014-12-01

    One way to address the growing problem of antimicrobial resistance is to revive old compounds that may have intrinsic lethal activity that is obscured by protective factors. Bicyclomycin is an old inhibitor of the Rho transcription terminator that by itself shows little rapid lethal activity. However, bicyclomycin participates in bacteriostatic synergy, which raises the possibility that conditions for lethal synergy may exist, perhaps through a suppression of protective factors. Bicyclomycin was combined with bacteriostatic inhibitors of gene expression, and bactericidal activity was measured with several cultured Gram-negative pathogens. When used alone, bicyclomycin failed to rapidly kill growing cultures of Escherichia coli; however, the additional presence of bacteriostatic concentrations of tetracycline, chloramphenicol or rifampicin led to rapid killing. Four other pathogen species, Acinetobacter baumannii, Klebsiella pneumoniae, Salmonella enterica serotype Typhimurium and Shigella dysenteriae, also exhibited enhanced killing when bicyclomycin was combined with tetracycline or rifampicin. This lethal synergy was achieved at low concentrations (slightly above the MIC) for all agents tested in combinations. Follow-up work with E. coli indicated that lethal synergy arose from a blockage of transcription elongation. Moreover, lethal synergy was reduced when bicyclomycin was added 60 min before tetracycline, suggesting that bicyclomycin induces a protective factor. The action of bicyclomycin illustrates the potential present in a largely abandoned antibacterial agent; it exhibits lethal synergy when coadministered with known, bacteriostatic inhibitors of gene expression. The identification of protective factors, which are currently uncharacterized, may reveal new ways to promote the lethal action of some old antibiotics. © The Author 2014. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved

  8. Sonographic features of lethal multiple pterygium syndrome at 14 weeks.

    Science.gov (United States)

    Chen, Min; Chan, Gavin Shueng Wai; Lee, Chin Peng; Tang, Mary Hoi Yin

    2005-06-01

    Lethal multiple pterygium syndrome is a rare inherited disorder. Previous reports suggest that the diagnosis may be based on prenatal sonographic demonstration of severe limb flexion, absence of fetal motion, and a large cystic hygroma in the second and third trimesters. We present the sonographic features and postmortem features of a fetus with lethal multiple pterygium syndrome at 13 weeks of gestation, which shows that the condition can possibly be diagnosed in the first trimester of pregnancy.

  9. Shock Dynamics in Stellar Outbursts. I. Shock Formation

    Energy Technology Data Exchange (ETDEWEB)

    Ro, Stephen; Matzner, Christopher D., E-mail: ro@astro.utoronto.ca [Department of Astronomy and Astrophysics, University of Toronto, 50 St. George Street, Toronto, ON M5S 3H4 (Canada)

    2017-05-20

    Wave-driven outflows and non-disruptive explosions have been implicated in pre-supernova outbursts, supernova impostors, luminous blue variable eruptions, and some narrow-line and superluminous supernovae. To model these events, we investigate the dynamics of stars set in motion by strong acoustic pulses and wave trains, focusing on nonlinear wave propagation, shock formation, and an early phase of the development of a weak shock. We identify the shock formation radius, showing that a heuristic estimate based on crossing characteristics matches an exact expansion around the wave front and verifying both with numerical experiments. Our general analytical condition for shock formation applies to one-dimensional motions within any static environment, including both eruptions and implosions. We also consider the early phase of shock energy dissipation. We find that waves of super-Eddington acoustic luminosity always create shocks, rather than damping by radiative diffusion. Therefore, shock formation is integral to super-Eddington outbursts.

  10. Grain destruction in interstellar shocks

    International Nuclear Information System (INIS)

    Seab, C.G.; Shull, J.M.

    1984-01-01

    One of the principal methods for removing grains from the Interstellar Medium is to destroy them in shock waves. Previous theoretical studies of shock destruction have generally assumed only a single size and type of grain; most do not account for the effect of the grain destruction on the structure of the shock. Earlier calculations have been improved in three ways: first, by using a ''complete'' grain model including a distribution of sizes and types of grains; second, by using a self-consistent shock structure that incorporates the changing elemental depletions as the grains are destroyed; and third, by calculating the shock-processed ultraviolet extinction curves for comparison with observations. (author)

  11. Bubble Dynamics and Shock Waves

    CERN Document Server

    2013-01-01

    This volume of the Shock Wave Science and Technology Reference Library is concerned with the interplay between bubble dynamics and shock waves. It is divided into four parts containing twelve chapters written by eminent scientists. Topics discussed include shock wave emission by laser generated bubbles (W Lauterborn, A Vogel), pulsating bubbles near boundaries (DM Leppinen, QX Wang, JR Blake), interaction of shock waves with bubble clouds (CD Ohl, SW Ohl), shock propagation in polydispersed bubbly liquids by model equations (K Ando, T Colonius, CE Brennen. T Yano, T Kanagawa,  M Watanabe, S Fujikawa) and by DNS (G Tryggvason, S Dabiri), shocks in cavitating flows (NA Adams, SJ Schmidt, CF Delale, GH Schnerr, S Pasinlioglu) together with applications involving encapsulated bubble dynamics in imaging (AA Doinikov, A Novell, JM Escoffre, A Bouakaz),  shock wave lithotripsy (P Zhong), sterilization of ships’ ballast water (A Abe, H Mimura) and bubbly flow model of volcano eruptions ((VK Kedrinskii, K Takayama...

  12. Chimeric anti-staphylococcal enterotoxin B antibodies and lovastatin act synergistically to provide in vivo protection against lethal doses of SEB.

    Directory of Open Access Journals (Sweden)

    Mulualem E Tilahun

    Full Text Available Staphylococcal enterotoxin B (SEB is one of a family of toxins secreted by Staphylococcus aureus that act as superantigens, activating a large fraction of the T-cell population and inducing production of high levels of inflammatory cytokines that can cause toxic shock syndrome (TSS and death. Extracellular engagement of the TCR of T-cells and class II MHC of antigen presenting cells by SEB triggers the activation of many intracellular signaling processes. We engineered chimeric antibodies to block the extracellular engagement of cellular receptors by SEB and used a statin to inhibit intracellular signaling. Chimeric human-mouse antibodies directed against different neutralizing epitopes of SEB synergistically inhibited its activation of human T-cells in vitro. In the in vivo model of lethal toxic shock syndrome (TSS in HLA-DR3 transgenic mice, two of these antibodies conferred significant partial protection when administered individually, but offered complete protection in a synergistic manner when given together. Similarly, in vivo, lovastatin alone conferred only partial protection from TSS similar to single anti-SEB antibodies. However, used in combination with one chimeric neutralizing anti-SEB antibody, lovastatin provided complete protection against lethal TSS in HLA-DR3 transgenic mice. These experiments demonstrate that in vivo protection against lethal doses of SEB can be achieved by a statin of proven clinical safety and chimeric human-mouse antibodies, agents now widely used and known to be of low immunogenicity in human hosts.

  13. Adjustable Shock Absorbers

    OpenAIRE

    Adamiec, Radek

    2012-01-01

    Bakalářská práce obsahuje přehled používaných tlumičů osobních automobilů, závodních automobilů a motocyklů. Jsou zde popsány systémy t lumením, konstrukce tlumičů a vidlic používaných u motocyklů. Dále je zde přehled prvků používaných u podvozků automobilů. This bachelor´s thesis contains the survey of the shock absorbers of passenger cars, racing cars and motorcycles. Are described damping systems, the design used shock absorbers and forks for motorcycles. Then there is the list of the e...

  14. Radiative relativistic shock adiabate

    International Nuclear Information System (INIS)

    Tsintsadze, L.N.; Nishikawa, K.

    1997-01-01

    The influences of thermal radiation on the state equation of shock waves, derived in the previous paper [L. N. Tsintsadze, Phys. Plasmas 2, 4462 (1995)], are studied and a series of relations of thermodynamic quantities that hold for shock waves are derived. It is shown that the presence of radiation can strongly change the compressibility of the plasma. It is well known that for polytropic gases the compressibility cannot change more than four times the initial value in the case of nonrelativistic temperatures. The numerical calculations show that there are no such restrictions, when the radiation energy exceeds the kinetic energy of the plasma. The ultrarelativistic temperature range is also covered in our numerical calculations. Also studied are the influences of the radiation on the PT and the TV diagrams. A significant modification due to radiation is found in every case studied. copyright 1997 American Institute of Physics

  15. POSTURAL SHOCK IN PREGNANCY

    Science.gov (United States)

    Wilkening, Ralph L.; Knauer, John; Larson, Roger K.

    1955-01-01

    Signs and symptoms of shock may be produced in some patients in late pregnancy by putting them in the dorsal recumbent posture. Change from this position will relieve the condition. The features of the supine hypotensive syndrome can be duplicated by applying pressure to the abdomen with the patient in a lateral position. The postural variations of venous pressure, blood pressure, and pulse appear to be due to obstruction of venous return from the lower portion of the body caused by the large uterus of late pregnancy compressing the vena cava. When shock is observed in a woman in late pregnancy, she should be turned to a lateral position before more active measures of treatment are begun. ImagesFigure 1. PMID:14351983

  16. Bow shock data analysis

    Science.gov (United States)

    Zipf, Edward C.; Erdman, Peeter W.

    1994-08-01

    The University of Pittsburgh Space Physics Group in collaboration with the Army Research Office (ARO) modeling team has completed a systematic organization of the shock and plume spectral data and the electron temperature and density measurements obtained during the BowShock I and II rocket flights which have been submitted to the AEDC Data Center, has verified the presence of CO Cameron band emission during the Antares engine burn and for an extended period of time in the post-burn plume, and have adapted 3-D radiation entrapment codes developed by the University of Pittsburgh to study aurora and other atmospheric phenomena that involve significant spatial effects to investigate the vacuum ultraviolet (VUV) and extreme ultraviolet (EUV) envelope surrounding the re-entry that create an extensive plasma cloud by photoionization.

  17. Shock Isolation Elements Testing for High Input Loadings. Volume III. Mechanical Shock Isolation Elements.

    Science.gov (United States)

    SHOCK ABSORBERS ), (*GUIDED MISSILE SILOS, SHOCK ABSORBERS ), (*SPRINGS, (*SHOCK(MECHANICS), REDUCTION), TORSION BARS, ELASTOMERS, DAMPING, EQUATIONS OF MOTION, MODEL TESTS, TEST METHODS, NUCLEAR EXPLOSIONS, HARDENING.

  18. Shock resistance testing

    International Nuclear Information System (INIS)

    Pouard, M.

    1984-03-01

    In the framework of mechanical tests and to answer the different requests for tests, the T.C.R (Transport Conditionnement et Retraitement) laboratory got test facilities. These installations allow to carry out tests of resistance to shocks, mainly at the safety level of components of nuclear power plants, mockups of transport casks for fuel elements and transport containers for radioactive materials. They include a tower and a catapult. This paper give a decription of the facilities and explain their operation way [fr

  19. On Modeling Risk Shocks

    OpenAIRE

    Dorofeenko, Victor; Lee, Gabriel; Salyer, Kevin; Strobel, Johannes

    2016-01-01

    Within the context of a financial accelerator model, we model time-varying uncertainty (i.e. risk shocks) through the use of a mixture Normal model with time variation in the weights applied to the underlying distributions characterizing entrepreneur productivity. Specifically, we model capital producers (i.e. the entrepreneurs) as either low-risk (relatively small second moment for productivity) and high-risk (relatively large second moment for productivity) and the fraction of both types is...

  20. The Shock Doctrine

    OpenAIRE

    Dionysios K. Solomos; Dimitrios N. Koumparoulis

    2011-01-01

    Naomi Klein attempts to redefine the economic history discovering the historical continuities and to reveal the neoliberal theory which functions via the utilization of specific “tools”. The state of shock is the key for the opponents of Chicago School and Milton Friedman in order for them to establish neoliberal policies and to promote the deregulated capitalism which includes less welfare state, less public sector, less regulation, weakened labor unions, privatizations and laissez-faire. Th...

  1. Characterization of shocked beryllium

    Directory of Open Access Journals (Sweden)

    Papin P.A.

    2012-08-01

    Full Text Available While numerous studies have investigated the low-strain-rate constitutive response of beryllium, the combined influence of high strain rate and temperature on the mechanical behavior and microstructure of beryllium has received limited attention over the last 40 years. In the current work, high strain rate tests were conducted using both explosive drive and a gas gun to accelerate the material. Prior studies have focused on tensile loading behavior, or limited conditions of dynamic strain rate and/or temperature. Two constitutive strength (plasticity models, the Preston-Tonks-Wallace (PTW and Mechanical Threshold Stress (MTS models, were calibrated using common quasi-static and Hopkinson bar data. However, simulations with the two models give noticeably different results when compared with the measured experimental wave profiles. The experimental results indicate that, even if fractured by the initial shock loading, the Be remains sufficiently intact to support a shear stress following partial release and subsequent shock re-loading. Additional “arrested” drive shots were designed and tested to minimize the reflected tensile pulse in the sample. These tests were done to both validate the model and to put large shock induced compressive loads into the beryllium sample.

  2. Selfsimilar time dependent shock structures

    International Nuclear Information System (INIS)

    Beck, R.; Drury, L.O.

    1985-01-01

    Diffusive shock acceleration as an astrophysical mechanism for accelerating charged particles has the advantage of being highly efficient. This means however that the theory is of necessity nonlinear; the reaction of the accelerated particles on the shock structure and the acceleration process must be self-consistently included in any attempt to develop a complete theory of diffusive shock acceleration. Considerable effort has been invested in attempting, at least partially, to do this and it has become clear that in general either the maximum particle energy must be restricted by introducing additional loss processes into the problem or the acceleration must be treated as a time dependent problem (Drury, 1984). It is concluded that stationary modified shock structures can only exist for strong shocks if additional loss processes limit the maximum energy a particle can attain. This is certainly possible and if it occurs the energy loss from the shock will lead to much greater shock compressions. It is however equally possible that no such processes exist and we must then ask what sort of nonstationary shock structure develops. The same argument which excludes stationary structures also rules out periodic solutions and indeed any solution where the width of the shock remains bounded. It follows that the width of the shock must increase secularly with time and it is natural to examine the possibility of selfsimilar time dependent solutions

  3. Selfsimilar time dependent shock structures

    Science.gov (United States)

    Beck, R.; Drury, L. O.

    1985-01-01

    Diffusive shock acceleration as an astrophysical mechanism for accelerating charged particles has the advantage of being highly efficient. This means however that the theory is of necessity nonlinear; the reaction of the accelerated particles on the shock structure and the acceleration process must be self-consistently included in any attempt to develop a complete theory of diffusive shock acceleration. Considerable effort has been invested in attempting, at least partially, to do this and it has become clear that in general either the maximum particle energy must be restricted by introducing additional loss processes into the problem or the acceleration must be treated as a time dependent problem (Drury, 1984). It is concluded that stationary modified shock structures can only exist for strong shocks if additional loss processes limit the maximum energy a particle can attain. This is certainly possible and if it occurs the energy loss from the shock will lead to much greater shock compressions. It is however equally possible that no such processes exist and we must then ask what sort of nonstationary shock structure develops. The ame argument which excludes stationary structures also rules out periodic solutions and indeed any solution where the width of the shock remains bounded. It follows that the width of the shock must increase secularly with time and it is natural to examine the possibility of selfsimilar time dependent solutions.

  4. Empirical complexities in the genetic foundations of lethal mutagenesis.

    Science.gov (United States)

    Bull, James J; Joyce, Paul; Gladstone, Eric; Molineux, Ian J

    2013-10-01

    From population genetics theory, elevating the mutation rate of a large population should progressively reduce average fitness. If the fitness decline is large enough, the population will go extinct in a process known as lethal mutagenesis. Lethal mutagenesis has been endorsed in the virology literature as a promising approach to viral treatment, and several in vitro studies have forced viral extinction with high doses of mutagenic drugs. Yet only one empirical study has tested the genetic models underlying lethal mutagenesis, and the theory failed on even a qualitative level. Here we provide a new level of analysis of lethal mutagenesis by developing and evaluating models specifically tailored to empirical systems that may be used to test the theory. We first quantify a bias in the estimation of a critical parameter and consider whether that bias underlies the previously observed lack of concordance between theory and experiment. We then consider a seemingly ideal protocol that avoids this bias-mutagenesis of virions-but find that it is hampered by other problems. Finally, results that reveal difficulties in the mere interpretation of mutations assayed from double-strand genomes are derived. Our analyses expose unanticipated complexities in testing the theory. Nevertheless, the previous failure of the theory to predict experimental outcomes appears to reside in evolutionary mechanisms neglected by the theory (e.g., beneficial mutations) rather than from a mismatch between the empirical setup and model assumptions. This interpretation raises the specter that naive attempts at lethal mutagenesis may augment adaptation rather than retard it.

  5. A multivariate model of stakeholder preference for lethal cat management.

    Science.gov (United States)

    Wald, Dara M; Jacobson, Susan K

    2014-01-01

    Identifying stakeholder beliefs and attitudes is critical for resolving management conflicts. Debate over outdoor cat management is often described as a conflict between two groups, environmental advocates and animal welfare advocates, but little is known about the variables predicting differences among these critical stakeholder groups. We administered a mail survey to randomly selected stakeholders representing both of these groups (n=1,596) in Florida, where contention over the management of outdoor cats has been widespread. We used a structural equation model to evaluate stakeholder intention to support non-lethal management. The cognitive hierarchy model predicted that values influenced beliefs, which predicted general and specific attitudes, which in turn, influenced behavioral intentions. We posited that specific attitudes would mediate the effect of general attitudes, beliefs, and values on management support. Model fit statistics suggested that the final model fit the data well (CFI=0.94, RMSEA=0.062). The final model explained 74% of the variance in management support, and positive attitudes toward lethal management (humaneness) had the largest direct effect on management support. Specific attitudes toward lethal management and general attitudes toward outdoor cats mediated the relationship between positive (pstakeholder intention to support non-lethal cat management. Our findings suggest that stakeholders can simultaneously perceive both positive and negative beliefs about outdoor cats, which influence attitudes toward and support for non-lethal management.

  6. [Septic shock in a patient with the Fournièr gangrene with fatal outcome].

    Science.gov (United States)

    Zonca, P; Mrázek, T; Matusek, A; Hajek, M; Stiglerová, S; Jurytko, A; Kucera, C; Nieslanik, M

    2009-07-01

    The authors present a case of a patient with developed Fournièr gangrene and septic shock. Fournièr gangrene belongs to the group of local non-specific infection of soft tissues (NSTI). Its incidence is relatively low, but the infection is extraordinary aggressive with a possible lethal end. 39 years old patient with 4 days history of Fournier gangrene's development was admitted in irreversible septic shock. The initial APACHE II score was 36. The delay in treatment was an important factor in the further course of illness with lethal end. Above the mentioned 39 years old patient died because of septic shock. The hemorrhagic cystitis was the original source of infection with further development of Fournièr gangrene according to the pathological record. We often come across all different kinds of stages of sepsis from the MODS to the septic shock for patients with Fournièr gangrene. Causal treatment should be started early. The local surgical excision and wide broad antibiotic administrations are basic treatments in the context of other treatment modalities according to the current patient's needs. The adjuvant hyperbaric oxygen treatment takes place in patients with Fournièr gangrene as well and is beneficial. The following factor even worsens the illness prognosis: delay in diagnostic, higher age, anorectal origin of infection, the amount of organ with dysfunction or failure, diabetes mellitus and significant immunodeficiency.

  7. Effects of lethal and non-lethal malaria on the mononuclear phagocyte system

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo Tosta

    1983-03-01

    Full Text Available The effects ofone non-lethal species ofmalarialparasite, Plasmodium yoelii, and one lethal species, P. berghei, on the mononuclear phagocyte system (MPS of BALB/c mice were studied. P. yoelii caused a greater and more sustained expansion and activation of the MPS, and the two major populations of spleen phagocytic cells-red pulp and marginal zone macrophages - exhibited a greater increase in numbers in this infection. During the course of P. berghei mataria, the spleen was progressively occupied by haematopoietic tissue and, at the terminal stage of infection, an extensive depletion of lymphocytes and macrophages was apparent. The possibility was suggested that the outcome of mataria may be inftuenced by the particular way the parasite interacts with the MPS.Estudou-se o efeito da infecção causada por espécie letal (Plasmodium berghei e não- letal (P. yoelii de plasmódio sobre o sistema de fagócitos mononucleares de camundongo BALB/c. O P. yoelii causou maior e mais prolongada expansão e ativação do sistema de macrófagos. As duas mais importantes populações de fagócitos esplênicos - macrófagos de polpa vermelha e da zona marginal - exibiam maior aumento do número de células nesta infecção. Durante a evolução da malária por P. berghei, o baço foi progressivamente ocupado por tecido hematopoiético e, na fase terminal da infecção, observou-se significativa depleção dos linfócitos e macrófagos esplênicos. Os dados apresentados indicam que a evolução da malária depende do tipo de interação entre o plasmódio e o sistema de fagócitos mononucleares.

  8. Analysis of time of death of prenatally lethal Steeloid mutations

    International Nuclear Information System (INIS)

    Rinchik, E.M.; Cummings, C.C.; Bangham, J.W.; Hunsicker, P.R.; Phipps, E.L.; Stelzner, K.F.

    1987-01-01

    Deletion mutations have been extremely useful in initiating the functional and molecular dissections of regions of the mouse genome. For the d-se and c regions, for example, it was observed that radiation mutations carrying lethal factors separable, by complementation analysis, from the primary d, se, or c mutation itself, could often be associated at both the genetic and molecular levels with multilocus chromosomal deletions. Since many of the Oak Ridge Sld mutations arose in radiation mutagenesis experiments, a substantial number may carry chromosomal deletions that involve the Sl locus in chromosome 10. Because of the great value of deletion mutations for the genetic and molecular analysis of chromosomal regions and complex genetic loci, they have initiated a series of experiments designed to test whether radiation-induced Sld mutations carry other lethal factors, in addition to the lethality caused by severe alleles of the Sl locus itself, as one prescreen for identifying Sld's that are caused by deletions

  9. The Effects of Anthrax Lethal Toxin on Host Barrier Function

    Directory of Open Access Journals (Sweden)

    David M. Frucht

    2011-06-01

    Full Text Available The pathological actions of anthrax toxin require the activities of its edema factor (EF and lethal factor (LF enzyme components, which gain intracellular access via its receptor-binding component, protective antigen (PA. LF is a metalloproteinase with specificity for selected mitogen-activated protein kinase kinases (MKKs, but its activity is not directly lethal to many types of primary and transformed cells in vitro. Nevertheless, in vivo treatment of several animal species with the combination of LF and PA (termed lethal toxin or LT leads to morbidity and mortality, suggesting that LT-dependent toxicity is mediated by cellular interactions between host cells. Decades of research have revealed that a central hallmark of this toxicity is the disruption of key cellular barriers required to maintain homeostasis. This review will focus on the current understanding of the effects of LT on barrier function, highlighting recent progress in establishing the molecular mechanisms underlying these effects.

  10. Risk shocks and housing markets

    OpenAIRE

    Dorofeenko, Viktor; Lee, Gabriel S.; Salyer, Kevin D.

    2010-01-01

    Abstract: This paper analyzes the role of uncertainty in a multi-sector housing model with financial frictions. We include time varying uncertainty (i.e. risk shocks) in the technology shocks that affect housing production. The analysis demonstratesthat risk shocks to the housing production sector are a quantitatively important impulse mechanism for the business cycle. Also, we demonstrate that bankruptcy costs act as an endogenous markup factor in housing prices; as a consequence, the volati...

  11. Early events of lethal action by tobramycin in Pseudomonas aeruginosa

    International Nuclear Information System (INIS)

    Raulston, J.E.

    1988-01-01

    The immediate activities of the aminoglycoside antibiotic, tobramycin, were investigated in Pseudomonas aeruginosa PAO1. The influence of carbon growth substate and the antibiotic exposure environment in the magnitude of activity were examined. Lethality by 8 μg/ml tobramycin occurred rapidly (1 to 3 minutes). The release of specific cellular components into the supernatant was associated with lethality. This material was initially detected as an increase in UV-absorbance. Magnesium in the reaction mixture provided protection against lethality and leakage, but did not reverse lethal damage after a 3 minute tobramycin treatment. Also, uptake of 3 H-tobramycin was reduced in the presence of magnesium. Cells grown with glucose as a carbon source were more susceptible than organic acid grown cells as was the rapidity and amount of cell damage. Analyses of the leakage material revealed a 2-fold increase of protein in the supernatant after a 1-3 minute treatment which paralleled lethality. A prominent 29 kDa protein was observed by SDS-PAGE in the released material, which has been identified as the periplasmic enzyme, β-lactamase. The immediate activities of tobramycin did not involve (i) release of overall cell protein, (ii) massive loss of total pool amino acids, (iii) cell lysis, (iv) inhibition of proline uptake, (v) release of lipopolysaccharide, or (vi) leakage of ATP. Electron microscopy showed no apparent damage after a 3 minute exposure. 40% inhibition of protein synthesis had occurred by 3 minutes of exposure, while release of UV-absorbing material and lethality were detectable after only 1 minute. Resistant cystic fibrosis isolates of P. aeruginosa did not leak under the same experimental conditions, but one of two susceptible strains examined did show increased UV-absorbance following treatment

  12. Impact of acute alcohol consumption on lethality of suicide methods.

    Science.gov (United States)

    Park, C Hyung Keun; Yoo, Seong Ho; Lee, Jaewon; Cho, Sung Joon; Shin, Min-Sup; Kim, Eun Young; Kim, Se Hyun; Ham, Keunsoo; Ahn, Yong Min

    2017-05-01

    The influence of acute alcohol consumption on the factors related to suicide remains understudied. Thus, the present study investigated the relationship between blood alcohol content (BAC) and the lethality of suicide methods. Autopsy data on 315 South Korean suicide completers with a positive BAC were collected from a nationwide pool between May 2015 and November 2015, and the methods were dichotomised as suicide methods of low lethality (SMLL; drug/chemical overdose and sharp objects, n=67) and suicide methods of high lethality (SMHL; everything else, n=243). BAC at the time of autopsy and various suicide-related factors of these two groups were compared with logistic regression analyses. Compared to suicide completers with a BAC in the lowest range of 0.011-0.049%, suicide completers with a BAC in the range of 0.150-0.199% were more likely to use SMHL (odds ratio [OR]: 3.644, 95% confidence interval [CI]: 1.221-10.874). Additionally, the adoption of SMHL was significantly associated with the absence of a psychiatric illness (OR: 0.433, 95% CI: 0.222-0.843) and a younger age; the OR for high BAC among subjects in their 40s was 0.266 (95% CI: 0.083-0.856); in their 50s, 0.183 (95% CI: 0.055-0.615); and in their 60s, 0.057 (95% CI: 0.015-0.216). The relationship between BAC and suicide method lethality was represented by a bell-shaped pattern in which suicide methods of high lethality were more likely to be used by suicide completers with mid-range BAC levels. The increased impulsivity and impairments in particular executive functions, including planning and organization, associated with acute alcohol use may influence the selection of a particular suicide method based on its lethality. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Lethals induced by γ-radiation in drosophila somatic cells

    International Nuclear Information System (INIS)

    Ivanov, A.I.

    1989-01-01

    Exposure of 3-hour drosophila male embryos to γ-radiation during the topographic segregation of the germ anlage nuclei caused recessive sex-linked lethals in somatic cells only. The selectivity of the screening was determined by the ratio of mutation frequencies induced in embryos and adult males. Analysis of lethal mutations shows that a minimal rate of the divergence between germinal and somatic patterns of the cell development is observed in the embryogenesis, the 3d instar larva and prepupa, and maximal in the 1st and 2nd larva and pupa

  14. Effective lethal mutagenesis of influenza virus by three nucleoside analogs.

    Science.gov (United States)

    Pauly, Matthew D; Lauring, Adam S

    2015-04-01

    Lethal mutagenesis is a broad-spectrum antiviral strategy that exploits the high mutation rate and low mutational tolerance of many RNA viruses. This approach uses mutagenic drugs to increase viral mutation rates and burden viral populations with mutations that reduce the number of infectious progeny. We investigated the effectiveness of lethal mutagenesis as a strategy against influenza virus using three nucleoside analogs, ribavirin, 5-azacytidine, and 5-fluorouracil. All three drugs were active against a panel of seasonal H3N2 and laboratory-adapted H1N1 strains. We found that each drug increased the frequency of mutations in influenza virus populations and decreased the virus' specific infectivity, indicating a mutagenic mode of action. We were able to drive viral populations to extinction by passaging influenza virus in the presence of each drug, indicating that complete lethal mutagenesis of influenza virus populations can be achieved when a sufficient mutational burden is applied. Population-wide resistance to these mutagenic agents did not arise after serial passage of influenza virus populations in sublethal concentrations of drug. Sequencing of these drug-passaged viral populations revealed genome-wide accumulation of mutations at low frequency. The replicative capacity of drug-passaged populations was reduced at higher multiplicities of infection, suggesting the presence of defective interfering particles and a possible barrier to the evolution of resistance. Together, our data suggest that lethal mutagenesis may be a particularly effective therapeutic approach with a high genetic barrier to resistance for influenza virus. Influenza virus is an RNA virus that causes significant morbidity and mortality during annual epidemics. Novel therapies for RNA viruses are needed due to the ease with which these viruses evolve resistance to existing therapeutics. Lethal mutagenesis is a broad-spectrum strategy that exploits the high mutation rate and the low

  15. Health shocks and risk aversion.

    Science.gov (United States)

    Decker, Simon; Schmitz, Hendrik

    2016-12-01

    We empirically assess whether a health shock influences individual risk aversion. We use grip strength data to obtain an objective health shock indicator. In order to account for the non-random nature of our data regression-adjusted matching is employed. Risk preferences are traditionally assumed to be constant. However, we find that a health shock increases individual risk aversion. The finding is robust to a series of sensitivity analyses and persists for at least four years after the shock. Income changes do not seem to be the driving mechanism. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Shock in the emergency department

    DEFF Research Database (Denmark)

    Holler, Jon Gitz; Henriksen, Daniel Pilsgaard; Mikkelsen, Søren

    2016-01-01

    BACKGROUND: The knowledge of the frequency and associated mortality of shock in the emergency department (ED) is limited. The aim of this study was to describe the incidence, all-cause mortality and factors associated with death among patients suffering shock in the ED. METHODS: Population...... failures. Outcomes were annual incidence per 100,000 person-years at risk (pyar), all-cause mortality at 0-7, and 8-90 days and risk factors associated with death. RESULTS: We identified 1646 of 438,191 (0.4 %) ED patients with shock at arrival. Incidence of shock increased from 53.8 to 80.6 cases per 100...

  17. Shock compression of diamond crystal

    OpenAIRE

    Kondo, Ken-ichi; Ahrens, Thomas J.

    1983-01-01

    Two shock wave experiments employing inclined mirrors have been carried out to determine the Hugoniot elastic limit (HEL), final shock state at 191 and 217 GPa, and the post-shock state of diamond crystal, which is shock-compressed along the intermediate direction between the and crystallographic axes. The HEL wave has a velocity of 19.9 ± 0.3 mm/µsec and an amplitude of 63 ± 28 GPa. An alternate interpretation of the inclined wedge mirror streak record suggests a ramp precursor wave and th...

  18. A Shocking Solar Nebula?

    OpenAIRE

    Liffman, Kurt

    2009-01-01

    It has been suggested that shock waves in the solar nebula formed the high temperature materials observed in meteorites and comets. It is shown that the temperatures at the inner rim of the solar nebula could have been high enough over a sufficient length of time to produce chondrules, CAIs, refractory dust grains and other high-temperature materials observed in comets and meteorites. The solar bipolar jet flow may have produced an enrichment of 16O in the solar nebula over time and the chond...

  19. Myths of "shock therapy".

    Science.gov (United States)

    Fink, M

    1977-09-01

    The author discusses the myths of the ECT process--that shock and the convulsion are essential, memory loss and brain damage are inescapable, and little is known of the process--and assesses the fallacies in these ideas. Present views of the ECT process suggest that its mode of action in depression may best be described as a prolonged form of diencephalic stimulation, particularly useful to affect the hypothalamic dysfunctions that characterize depressive illness. The author emphasizes the need for further study of this treatment modality and for self-regulation by the profession.

  20. Gravitational shock waves and extreme magnetomaterial shock waves

    International Nuclear Information System (INIS)

    Lichnerowicz, Andre.

    1975-01-01

    Within an astrophysical context corresponding to high densities, a self-gravitating model is studied, which is the set of an extreme material medium of infinite conductivity and of a magnetic field. Corresponding shock waves generate necessarily, in general, gravitational shock waves [fr

  1. Shock Producers and Shock Absorbers in the Crisis

    OpenAIRE

    Sinn, Hans-Werner

    2009-01-01

    It is not surprising that the U.S. has been by far the world’s largest shock producer in this crisis. The big shock absorbers on the other hand were Japan, Russia and Germany, whose exports shrank more than their imports.

  2. Simulations of Converging Shock Collisions for Shock Ignition

    Science.gov (United States)

    Sauppe, Joshua; Dodd, Evan; Loomis, Eric

    2016-10-01

    Shock ignition (SI) has been proposed as an alternative to achieving high gain in inertial confinement fusion (ICF) targets. A central hot spot below the ignition threshold is created by an initial compression pulse, and a second laser pulse drives a strong converging shock into the fuel. The collision between the rebounding shock from the compression pulse and the converging shock results in amplification of the converging shock and increases the hot spot pressure above the ignition threshold. We investigate shock collision in SI drive schemes for cylindrical targets with a polystyrene foam interior using radiation-hydrodynamics simulations with the RAGE code. The configuration is similar to previous targets fielded on the Omega laser. The CH interior results in a lower convergence ratio and the cylindrical geometry facilitates visualization of the shock transit using an axial X-ray backlighter, both of which are important for comparison to potential experimental measurements. One-dimensional simulations are used to determine shock timing, and the effects of low mode asymmetries in 2D computations are also quantified. LA-UR-16-24773.

  3. 30th International Symposium on Shock Waves

    CERN Document Server

    Sadot, Oren; Igra, Ozer

    2017-01-01

    These proceedings collect the papers presented at the 30th International Symposium on Shock Waves (ISSW30), which was held in Tel-Aviv Israel from July 19 to July 24, 2015. The Symposium was organized by Ortra Ltd. The ISSW30 focused on the state of knowledge of the following areas: Nozzle Flow, Supersonic and Hypersonic Flows with Shocks, Supersonic Jets, Chemical Kinetics, Chemical Reacting Flows, Detonation, Combustion, Ignition, Shock Wave Reflection and Interaction, Shock Wave Interaction with Obstacles, Shock Wave Interaction with Porous Media, Shock Wave Interaction with Granular Media, Shock Wave Interaction with Dusty Media, Plasma, Magnetohyrdrodynamics, Re-entry to Earth Atmosphere, Shock Waves in Rarefied Gases, Shock Waves in Condensed Matter (Solids and Liquids), Shock Waves in Dense Gases, Shock Wave Focusing, Richtmyer-Meshkov Instability, Shock Boundary Layer Interaction, Multiphase Flow, Blast Waves, Facilities, Flow Visualization, and Numerical Methods. The two volumes serve as a reference ...

  4. Perforated appendicitis presenting as a thigh abscess: A lethal ...

    African Journals Online (AJOL)

    Typical cases of acute appendicitis have excellent treatment outcomes, if managed appropriately.1 We discuss an unusual case of perforated retrocaecal appendicitis that presented as a right thigh abscess without prominent abdominal symptoms, which highlights the lethal nature of advanced appendicitis even when ...

  5. Dominant-lethal mutations and heritable translocations in mice

    International Nuclear Information System (INIS)

    Generoso, W.M.

    1983-01-01

    Chromosome aberrations are a major component of radiation or chemically induced genetic damage in mammalian germ cells. The types of aberration produced are dependent upon the mutagen used and the germ-cell stage treated. For example, in male meiotic and postmeiotic germ cells certain alkylating chemicals induce both dominant-lethal mutations and heritable translocations while others induce primarily dominant-lethal mutations. Production of these two endpoints appears to be determined by the stability of alkylation products with the chromosomes. If the reaction products are intact in the male chromosomes at the time of sperm entry, they may be repaired in fertilized eggs. If repair is not effected and the alkylation products persist to the time of pronuclear chromosome replication, they lead to chromatid-type aberrations and eventually to dominant-lethality. The production of heritable translocations, on the other hand, requires a transformation of unstable alkylation products into suitable intermediate lesions. The process by which these lesions are converted into chromosome exchange within the male genome takes place after sperm enters the egg but prior to the time of pronuclear chromosome replication (i.e., chromosome-type). Thus, dominant-lethal mutations result from both chromatid- and chromosome-type aberrations while heritable translocations result primarily from the latter type. DNA target sites associated with the production of these two endpoints are discussed

  6. The "Lethal Chamber": Further Evidence of the Euthanasia Option.

    Science.gov (United States)

    Elks, Martin A.

    1993-01-01

    Historical discussions of the euthanasia or "lethal chamber" option in relation to people with mental retardation are presented. The paper concludes that eugenic beliefs in the primacy of heredity over environment and the positive role of natural selection may have condoned the poor conditions characteristic of large, segregated institutions and…

  7. Papaya Lethal Yellowing Virus (PLYV) Infects Vasconcellea cauliflora

    NARCIS (Netherlands)

    Amaral, P.P.R.; Resende, de R.O.; Souza, M.T.

    2006-01-01

    Papaya lethal yellowing virus (PLYV) é um dos três vírus descritos infectando mamoeiros (Carica papaya L.) no Brasil. Vasconcellea cauliflora (Jacq.) A. DC., antes denominada de Carica cauliflora (Jacq.), é uma reconhecida fonte de resistência natural ao Papaya ringspot virus (PRSV), causador da

  8. Dominant-lethal mutations and heritable translocations in mice

    Energy Technology Data Exchange (ETDEWEB)

    Generoso, W.M.

    1983-01-01

    Chromosome aberrations are a major component of radiation or chemically induced genetic damage in mammalian germ cells. The types of aberration produced are dependent upon the mutagen used and the germ-cell stage treated. For example, in male meiotic and postmeiotic germ cells certain alkylating chemicals induce both dominant-lethal mutations and heritable translocations while others induce primarily dominant-lethal mutations. Production of these two endpoints appears to be determined by the stability of alkylation products with the chromosomes. If the reaction products are intact in the male chromosomes at the time of sperm entry, they may be repaired in fertilized eggs. If repair is not effected and the alkylation products persist to the time of pronuclear chromosome replication, they lead to chromatid-type aberrations and eventually to dominant-lethality. The production of heritable translocations, on the other hand, requires a transformation of unstable alkylation products into suitable intermediate lesions. The process by which these lesions are converted into chromosome exchange within the male genome takes place after sperm enters the egg but prior to the time of pronuclear chromosome replication (i.e., chromosome-type). Thus, dominant-lethal mutations result from both chromatid- and chromosome-type aberrations while heritable translocations result primarily from the latter type. DNA target sites associated with the production of these two endpoints are discussed.

  9. Fighting Lethal Yellowing Disease for Coconut Farmers (CIFSRF ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Copra is the dried kernel of the coconut, which is used to extract coconut oil. Coconut is the main income source for the coastal region's poor farmers. Over the past 10 years, Côte d'Ivoire lethal yellowing disease has destroyed more than 350 hectares of coconut and caused losses of 12,000 tons of copra per year.

  10. Why the United States Must Adopt Lethal Autonomous Weapon Systems

    Science.gov (United States)

    2017-05-25

    intelligence , Lethal Autonomous Weapon Systems, energy production, energy storage, three-dimensional printing , bandwidth improvements, computer...views on the morality of artificial intelligence (AI) and robotics technology. Eastern culture sees artificial intelligence as an economic savior...capable of improving their society. In contrast, Western culture regards artificial intelligence with paranoia, anxiety, and skepticism. As Eastern

  11. Molecular diagnostics of interstellar shocks

    International Nuclear Information System (INIS)

    Hartquist, T.W.; Oppenheimer, M.; Dalgarno, A.

    1980-01-01

    The chemistry of molecules in shocked regions of the interstellar gas is considered and calculations are carried out for a region subjected to a shock at a velocity of 8 km s -1 Substantial enhancements are predicted in the concentrations of the molecules H 2 S, SO, and SiO compared to those anticipated in cold interstellar clouds

  12. Molecular diagnostics of interstellar shocks

    Science.gov (United States)

    Hartquist, T. W.; Dalgarno, A.; Oppenheimer, M.

    1980-02-01

    The chemistry of molecules in shocked regions of the interstellar gas is considered and calculations are carried out for a region subjected to a shock at a velocity of 8 km/sec. Substantial enhancements are predicted in the concentrations of the molecules H2S, SO, and SiO compared to those anticipated in cold interstellar clouds.

  13. How Culture Shock Affects Communication.

    Science.gov (United States)

    Barna, LaRay M.

    The paper defines the term "culture shock" and discusses the changes that this state can make in a person's behavior. Culture shock refers to the emotional and physiological reaction of high activation that is brought about by sudden immersion in a new culture. Because one's own culture shields one from the unknown and reduces the need to make…

  14. Molecular diagnostics of interstellar shocks

    Science.gov (United States)

    Hartquist, T. W.; Dalgarno, A.; Oppenheimer, M.

    1980-01-01

    The chemistry of molecules in shocked regions of the interstellar gas is considered and calculations are carried out for a region subjected to a shock at a velocity of 8 km/sec. Substantial enhancements are predicted in the concentrations of the molecules H2S, SO, and SiO compared to those anticipated in cold interstellar clouds.

  15. Shock wave treatment in medicine

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Biosciences; Volume 30; Issue 2 ... In the present paper we discuss the basic theory and application of shock waves and its history in medicine. The idea behind using shock wave therapy for orthopedic diseases is the stimulation of healing in tendons, surrounding tissue and bones. This is a ...

  16. Shock wave treatment in medicine

    Indian Academy of Sciences (India)

    Unknown

    to open surgery, the cost of the ESWT is very reasonable. But nevertheless it is necessary to improve the basic un ... In second group, shock waves are used to measure distances because of the low energy loss over large distances ... pared to a piezoelectric hydrophone. The rise time of an electrohydraulic generated shock ...

  17. Numerical modeling of slow shocks

    International Nuclear Information System (INIS)

    Winske, D.

    1987-01-01

    This paper reviews previous attempt and the present status of efforts to understand the structure of slow shocks by means of time dependent numerical calculations. Studies carried out using MHD or hybrid-kinetic codes have demonstrated qualitative agreement with theory. A number of unresolved issues related to hybrid simulations of the internal shock structure are discussed in some detail. 43 refs., 8 figs

  18. Dynamic shock wave: hammer blow

    International Nuclear Information System (INIS)

    Lackme, Claude

    1978-01-01

    The general properties of shocks, their generation and the conditions of reflexion to an interface are dealt with in turn. By then applying these concepts to a liquid column and its environment (wall, free area, closing devices) the hammer blow is presented as being a relatively weak shock [fr

  19. Slow shocks and their transition to fast shocks in the inner solar wind

    International Nuclear Information System (INIS)

    Wang, Y.C.

    1987-01-01

    The jump conditions of MHD shocks may be directly calculated as functions of three upstream conditions: the shock Alfven number based on the normal component of the relative shock speed, the shock angle, and the plasma β value. The shock Alfven number is less than 1 for a slow shock and greater than 1 for a fast shock. A traveling, forward shock can be a slow shock in coronal space, where the Alfven speed is of the order of 1000 km/s. The surface of a forward slow shock has a bow-shaped geometry with its nose facing toward the sun. The decrease in the Alfven speed at increasing heliocentric distance causes the shock Alfven number of a forward slow shock to become greater than 1, and the shock eventually evolves from a slow shock into a fast shock. During the transition the shock system consists of a slow shock, a fast shock, and a rotational discontinuity. They intersect along a closed transition line. As the system moves outward from the sun, the area enclosed by the transition line expands, the fast shock grows stronger, and the slow shock becomes weaker. Eventually, the slow shock diminishes, and the entire shock system evolves into a forward fast shock. copyrightAmerican Geophysical Union 1987

  20. Shocking matter to extreme conditions

    International Nuclear Information System (INIS)

    Gupta, Y.M.; Sharma, S.M.

    1997-01-01

    A good understanding of the thermodynamic response of matter at high compression and high energy densities is important to several areas of physics. Shock-wave experiments are uniquely suited for obtaining data at extreme conditions, and a shock-compressed matter can be viewed as a condensed system with or without dissociation or as a strongly coupled plasma. This article reviews work by Da Silva et al. in which irradiances ranging from 5x10 superscript 12 to 2x10 superscript 14 W/cm 2 were used to generate 8- to 10-ns square pulses in liquid deuterium. The authors demonstrated negligible pre-heating of the sample, steady propagation of the shock wave, and direct determination of the shock wave velocity along with particle velocity and density in the shocked state. Da Silva et al. results are compared with models and other experimental information, and the usefulness of the data in other areas is assessed. 11 refs., 1 fig

  1. Electron transport and shock ignition

    Energy Technology Data Exchange (ETDEWEB)

    Bell, A R; Tzoufras, M, E-mail: t.bell1@physics.ox.ac.uk [Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU (United Kingdom)

    2011-04-15

    Inertial fusion energy (IFE) offers one possible route to commercial energy generation. In the proposed 'shock ignition' route to fusion, the target is compressed at a relatively low temperature and then ignited using high intensity laser irradiation which drives a strong converging shock into the centre of the fuel. With a series of idealized calculations we analyse the electron transport of energy into the target, which produces the pressure responsible for driving the shock. We show that transport in shock ignition lies near the boundary between ablative and heat front regimes. Moreover, simulations indicate that non-local effects are significant in the heat front regime and might lead to increased efficiency by driving the shock more effectively and reducing heat losses to the plasma corona.

  2. Oscillating nonlinear acoustic shock waves

    DEFF Research Database (Denmark)

    Gaididei, Yuri; Rasmussen, Anders Rønne; Christiansen, Peter Leth

    2016-01-01

    We investigate oscillating shock waves in a tube using a higher order weakly nonlinear acoustic model. The model includes thermoviscous effects and is non isentropic. The oscillating shock waves are generated at one end of the tube by a sinusoidal driver. Numerical simulations show that at resona......We investigate oscillating shock waves in a tube using a higher order weakly nonlinear acoustic model. The model includes thermoviscous effects and is non isentropic. The oscillating shock waves are generated at one end of the tube by a sinusoidal driver. Numerical simulations show...... polynomial in the space and time variables, we find analytical approximations to the observed single shock waves in an infinitely long tube. Using perturbation theory for the driven acoustic system approximative analytical solutions for the off resonant case are determined....

  3. Influence of temperature and pressure on the lethality of ultrasound

    International Nuclear Information System (INIS)

    Raso, J.; Pagan, R.; Condon, S.; Sala, F.J.

    1998-01-01

    A specially designed resistometer was constructed, and the lethal effect on Yersinia enterocolitica of ultrasonic waves (UW) at different static pressures (manosonication [MS]) and of combined heat-UW under pressure treatments (manothermosonication [MTS]) was investigated. During MS treatments at 30 degrees C and 200 kPa, the increase in the amplitude of UW of 20 kHz from 21 to 150 micrometers exponentially decreased decimal reduction time values (D(MS)) from 4 to 0.37 min. When pressure was increased from 0 to 600 kPa at a constant amplitude (150 micrometers) and temperature (30 degrees C), D(MS) values decreased from 1.52 to 0.20 min. The magnitude of this decrease in D(MS) declined progressively as pressure was increased. The influence of pressure on D(MS) values was greater with increased amplitude of UW. Pressure alone of as much as 600 kPa did not influence the heat resistance of Y. enterocolitica (D60 = 0.094; zeta = 5.65). At temperatures of as much as 58 degrees C, the lethality of UW under pressure was greater than that of heat treatment alone at the same temperature. At higher temperatures, this difference disappeared. Heat and UW under pressure seemed to act independently. The lethality of MTS treatments appeared to result from the added effects of UW under pressure and the lethal effect of heat. The individual contributions of heat and of UW under pressure to the total lethal effect of MTS depended on temperature. The inactivating effect of UW was not due to titanium particles eroded from the sonication horn. The addition to the MS media of cysteamine did not increase the resistance of Y. enterocolitica to MS treatment. MS treatment caused cell disruption

  4. Annotating novel genes by integrating synthetic lethals and genomic information

    Directory of Open Access Journals (Sweden)

    Faty Mahamadou

    2008-01-01

    Full Text Available Abstract Background Large scale screening for synthetic lethality serves as a common tool in yeast genetics to systematically search for genes that play a role in specific biological processes. Often the amounts of data resulting from a single large scale screen far exceed the capacities of experimental characterization of every identified target. Thus, there is need for computational tools that select promising candidate genes in order to reduce the number of follow-up experiments to a manageable size. Results We analyze synthetic lethality data for arp1 and jnm1, two spindle migration genes, in order to identify novel members in this process. To this end, we use an unsupervised statistical method that integrates additional information from biological data sources, such as gene expression, phenotypic profiling, RNA degradation and sequence similarity. Different from existing methods that require large amounts of synthetic lethal data, our method merely relies on synthetic lethality information from two single screens. Using a Multivariate Gaussian Mixture Model, we determine the best subset of features that assign the target genes to two groups. The approach identifies a small group of genes as candidates involved in spindle migration. Experimental testing confirms the majority of our candidates and we present she1 (YBL031W as a novel gene involved in spindle migration. We applied the statistical methodology also to TOR2 signaling as another example. Conclusion We demonstrate the general use of Multivariate Gaussian Mixture Modeling for selecting candidate genes for experimental characterization from synthetic lethality data sets. For the given example, integration of different data sources contributes to the identification of genetic interaction partners of arp1 and jnm1 that play a role in the same biological process.

  5. Shock waves & explosions

    CERN Document Server

    Sachdev, PL

    2004-01-01

    Understanding the causes and effects of explosions is important to experts in a broad range of disciplines, including the military, industrial and environmental research, aeronautic engineering, and applied mathematics. Offering an introductory review of historic research, Shock Waves and Explosions brings analytic and computational methods to a wide audience in a clear and thorough way. Beginning with an overview of the research on combustion and gas dynamics in the 1970s and 1980s, the author brings you up to date by covering modeling techniques and asymptotic and perturbative methods and ending with a chapter on computational methods.Most of the book deals with the mathematical analysis of explosions, but computational results are also included wherever they are available. Historical perspectives are provided on the advent of nonlinear science, as well as on the mathematical study of the blast wave phenomenon, both when visualized as a point explosion and when simulated as the expansion of a high-pressure ...

  6. Analysis of shock implosion

    Energy Technology Data Exchange (ETDEWEB)

    Mishkin, E.A.; Alejaldre, C. (Polytechnic Inst. of New York, Brooklyn (USA))

    1984-06-01

    An imploding shock wave, coming from infinity, moves through an ideal gas with the adiabatic constant ..gamma... To define a single-valued self-similar coefficient over the whole classical interval 1<..gamma..

  7. The cosmic-ray shock structure problem for relativistic shocks

    Science.gov (United States)

    Webb, G. M.

    1985-01-01

    The time asymptotic behaviour of a relativistic (parallel) shock wave significantly modified by the diffusive acceleration of cosmic-rays is investigated by means of relativistic hydrodynamical equations for both the cosmic-rays and thermal gas. The form of the shock structure equation and the dispersion relation for both long and short wavelength waves in the system are obtained. The dependence of the shock acceleration efficiency on the upstream fluid spped, long wavelength Mach number and the ratio N = P sub co/cP sub co+P sub go)(Psub co and P sub go are the upstream cosmic-ray and thermal gas pressures respectively) are studied.

  8. Cosmic-ray shock acceleration in oblique MHD shocks

    Science.gov (United States)

    Webb, G. M.; Drury, L. OC.; Volk, H. J.

    1986-01-01

    A one-dimensional, steady-state hydrodynamical model of cosmic-ray acceleration at oblique MHD shocks is presented. Upstream of the shock the incoming thermal plasma is subject to the adverse pressure gradient of the accelerated particles, the J x B force, as well as the thermal gas pressure gradient. The efficiency of the acceleration of cosmic-rays at the shock as a function of the upstream magnetic field obliquity and upstream plasma beta is investigated. Astrophysical applications of the results are briefly discussed.

  9. Pressure resistance of cold-shocked Escherichia coli O157:H7 in ground beef, beef gravy and peptone water.

    Science.gov (United States)

    Baccus-Taylor, G S H; Falloon, O C; Henry, N

    2015-06-01

    (i) To study the effects of cold shock on Escherichia coli O157:H7 cells. (ii) To determine if cold-shocked E. coli O157:H7 cells at stationary and exponential phases are more pressure-resistant than their non-cold-shocked counterparts. (iii) To investigate the baro-protective role of growth media (0·1% peptone water, beef gravy and ground beef). Quantitative estimates of lethality and sublethal injury were made using the differential plating method. There were no significant differences (P > 0·05) in the number of cells killed; cold-shocked or non-cold-shocked. Cells grown in ground beef (stationary and exponential phases) experienced lowest death compared with peptone water and beef gravy. Cold-shock treatment increased the sublethal injury to cells cultured in peptone water (stationary and exponential phases) and ground beef (exponential phase), but decreased the sublethal injury to cells in beef gravy (stationary phase). Cold shock did not confer greater resistance to stationary or exponential phase cells pressurized in peptone water, beef gravy or ground beef. Ground beef had the greatest baro-protective effect. Real food systems should be used in establishing food safety parameters for high-pressure treatments; micro-organisms are less resistant in model food systems, the use of which may underestimate the organisms' resistance. © 2015 The Society for Applied Microbiology.

  10. Chondrule destruction in nebular shocks

    Energy Technology Data Exchange (ETDEWEB)

    Jacquet, Emmanuel; Thompson, Christopher, E-mail: ejacquet@mnhn.fr [Canadian Institute for Theoretical Astrophysics, University of Toronto, 60 St George Street, Toronto, ON M5S 3H8 (Canada)

    2014-12-10

    Chondrules are millimeter-sized silicate spherules ubiquitous in primitive meteorites, but whose origin remains mysterious. One of the main proposed mechanisms for producing them is melting of solids in shock waves in the gaseous protoplanetary disk. However, evidence is mounting that chondrule-forming regions were enriched in solids well above solar abundances. Given the high velocities involved in shock models, destructive collisions would be expected between differently sized grains after passage of the shock front as a result of differential drag. We investigate the probability and outcome of collisions of particles behind a one-dimensional shock using analytic methods as well as a full integration of the coupled mass, momentum, energy, and radiation equations. Destruction of protochondrules seems unavoidable for solid/gas ratios ε ≳ 0.1, and possibly even for solar abundances because of 'sandblasting' by finer dust. A flow with ε ≳ 10 requires much smaller shock velocities (∼2 versus 8 km s{sup –1}) in order to achieve chondrule-melting temperatures, and radiation trapping allows slow cooling of the shocked fragments. Initial destruction would still be extensive; although re-assembly of millimeter-sized particles would naturally occur by grain sticking afterward, the compositional heterogeneity of chondrules may be difficult to reproduce. We finally note that solids passing through small-scale bow shocks around few kilometer-sized planetesimals might experience partial melting and yet escape fragmentation.

  11. A quick method for testing recessive lethal damage with a diploid strain of Aspergillus nidulans

    International Nuclear Information System (INIS)

    Morpurgo, G.; Puppo, S.; Gualandi, G.; Conti, L.

    1978-01-01

    A simple method capable of detecting recessive lethal damage in a diploid strain of Aspergillus nidulans is described. The method scores the recessive lethals on the 1st, the 3rd and the 5th chromosomes, which represent about 40% of the total map of A. nidulans. Two examples of induced lethals, with ultraviolet irradiation and methyl methanesulfonate are shown. The frequency of lethals may reach 36% of the total population with UV irradiation. (Auth.)

  12. Humanitarian Algorithms : A Codified Key Safety Switch Protocol for Lethal Autonomy

    OpenAIRE

    Nyagudi, Nyagudi Musandu

    2014-01-01

    With the deployment of lethal autonomous weapons, there is the requirement that any such platform complies with the precepts of International Humanitarian Law. Humanitarian Algorithms[9: p. 9] ensure that lethal autonomous weapon systems perform military/security operations, within the confines of International Humanitarian Law. Unlike other existing techniques of regulating lethal autonomy this scheme advocates for an approach that enables Machine Learning. Lethal autonomous weapons must be ...

  13. Acquired thermotolerance and heat shock in the extremely thermophilic archaebacterium Sulfolobus sp. strain B12.

    Science.gov (United States)

    Trent, J D; Osipiuk, J; Pinkau, T

    1990-03-01

    The extreme thermophile Sulfolobus sp. strain B12 exhibits an acquired thermotolerance response. Thus, survival of cells from a 70 degrees C culture at the lethal temperature of 92 degrees C was enhanced by as much as 6 orders of magnitude over a 2-h period if the culture was preheated to 88 degrees C for 60 min or longer before being exposed to the lethal temperature. In eubacteria and eucaryotes, acquired thermotolerance correlates with the induced synthesis of a dozen or so proteins known as heat shock proteins. In this Sulfolobus species, it correlates with the preferential synthesis of primarily one major protein (55 kilodaltons) and, to a much lesser extent, two minor proteins (28 and 35 kilodaltons). Since the synthesis of all other proteins was radically reduced and these proteins were apparently not degraded or exported, their relative abundance within the cell increased during the time the cells were becoming thermotolerant. They could not yet be related to known heat shock proteins. In immunoassays, they were not cross-reactive with antibodies against heat shock proteins from Escherichia coli (DnaK and GroE), which are highly conserved between eubacteria and eucaryotes. However, it appears that if acquired thermotolerance depends on the synthesis of protective proteins, then in this extremely thermophilic archaebacterium it depends primarily on one protein.

  14. Simulation of mechanical shock environments

    International Nuclear Information System (INIS)

    Lalanne, Christian.

    1975-07-01

    Shocks can produce a severe mechanical environment which must be taken into account when designing and developing new equipments. After some mathematical (Laplace and Fourier transforms) and mechanical recalls (response of a one degree freedom system to a sinusoidal excitation), different analysis methods are compared, these methods being the most used now to compare relative severities of tests and establish specifications. A few chapter deal with the different properties of simple, easy to produce, shock shapes. Then some now-in-use programmators or shock-machines specifications are shown. A final chapter concerns acceleration transducers [fr

  15. Particle acceleration in modified shocks

    International Nuclear Information System (INIS)

    Drury, L.O'C.; Axford, W.I.; Summers, D.

    1982-01-01

    Efficient particle acceleration in shocks must modify the shock structure with consequent changes in the particle acceleration. This effect is studied and analytic solutions are found describing the diffusive acceleration of particles with momentum independent diffusion coefficients in hyperbolic tangent type velocity transitions. If the input particle spectrum is a delta function, the shock smoothing replaces the truncated power-law downstream particle spectrum by a more complicated form, but one which has a power-law tail at high momenta. For a cold plasma this solution can be made completely self-consistent. Some problems associated with momentum dependent diffusion coefficients are discussed. (author)

  16. INTERFERENCE OF COUNTERPROPAGATING SHOCK WAVES

    Directory of Open Access Journals (Sweden)

    P. V. Bulat

    2015-03-01

    Full Text Available The subject of study. We examined the interaction of counterpropagating shock waves. The necessity of counterpropagating shock waves studying occurs at designing of high Mach number modern internal compression air intakes, Ramjets with subsonic and supersonic combustion, in asymmetrical supersonic nozzles and in some other cases. In a sense, this problem is a generalization of the case of an oblique shock reflection from the wall or from the plane of symmetry. With the renewed vigor, the interest to this problem emerged at the end of the 90s. This was due to the start of the programs for flight study at hypersonic speeds. The first experiments performed with air intakes, which realized the interaction of counterpropagating shock waves have shown that the change in flow velocity is accompanied by abrupt alteration of shock-wave structure, the occurrence of nonstationary and oscillatory phenomena. With an increase of flow velocity these phenomena undesirable for aircraft structure became more marked. The reason is that there are two fundamentally different modes of interaction of counterpropagating shock waves: a four-wave regular and a five-wave irregular. The transition from one mode to another can be nonstationary abrupt or gradual, it can also be accompanied by hysteresis. Main results. Criteria for the transition from regular reflection of counterpropagating shock waves to irregular are described: the criterion of von Neumann and the stationary Mach configuration criterion. We described areas in which the transition from one reflection type to another is possible only in abrupt way, as well as areas of possible gradual transition. Intensity dependences of the reflected shock waves from the intensity of interacting counterpropagating shocks were given. Qualitative pictures of shock-wave structures arising from the interaction of counterpropagating shock waves were shown. Calculation results of the intensity of outgoing gas

  17. Particle acceleration in modified shocks

    Energy Technology Data Exchange (ETDEWEB)

    Drury, L.O' C. (Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany, F.R.)); Axford, W.I. (Max-Planck-Institut fuer Aeronomie, Katlenburg-Lindau (Germany, F.R.)); Summers, D. (Memorial Univ. of Newfoundland, St. John' s (Canada))

    1982-03-01

    Efficient particle acceleration in shocks must modify the shock structure with consequent changes in the particle acceleration. This effect is studied and analytic solutions are found describing the diffusive acceleration of particles with momentum independent diffusion coefficients in hyperbolic tangent type velocity transitions. If the input particle spectrum is a delta function, the shock smoothing replaces the truncated power-law downstream particle spectrum by a more complicated form, but one which has a power-law tail at high momenta. For a cold plasma this solution can be made completely self-consistent. Some problems associated with momentum dependent diffusion coefficients are discussed.

  18. Shocks in the Early Universe.

    Science.gov (United States)

    Pen, Ue-Li; Turok, Neil

    2016-09-23

    We point out a surprising consequence of the usually assumed initial conditions for cosmological perturbations. Namely, a spectrum of Gaussian, linear, adiabatic, scalar, growing mode perturbations not only creates acoustic oscillations of the kind observed on very large scales today, it also leads to the production of shocks in the radiation fluid of the very early Universe. Shocks cause departures from local thermal equilibrium as well as create vorticity and gravitational waves. For a scale-invariant spectrum and standard model physics, shocks form for temperatures 1  GeVUniverse as early as 10^{-30}  sec after the big bang.

  19. The effects of drying following heat shock exposure of the desert moss Syntrichia caninervis.

    Science.gov (United States)

    Xu, Shu-Jun; Liu, Chun-Jiang; Jiang, Ping-An; Cai, Wei-Min; Wang, Yan

    2009-03-15

    Desert mosses are components of biological soil crusts (BSCs) and their ecological functions make assessment and protection of these mosses a high-ranking management priority in desert regions. Drying is thought to be useful for desert mosses surviving heat shock. In this study, we investigated the role of drying by monitoring the responses of physiological characters and asexual reproduction in the typical desert moss Syntrichia caninervis. Heat significantly decreased chlorophyll content and weakened rapid recovery of photochemical activity, and increased carotenoid content and membrane permeability. Lethal temperatures significantly destroyed shoot regeneration potential. In comparison with heat alone, drying significantly increased protonema emergence time and depressed protonema emergence area. Drying combined with heat accelerated water loss, followed by a decrease of photosynthetic activity. Drying had different influences on membrane permeability at different temperatures. When moss leaves were subjected to a combined stress of drying and heat shock, photosynthesis was maintained mainly due to the effects of drying on physiological activity although the cellular morphological integrity was affected. Drying caused opposing effects on moss physiological and reproductive characteristics. On the one hand, drying caused a positive synergistic effect with heat shock when the temperature was below 40 degrees C. On the other hand, drying showed antagonism with heat shock when the moss was subjected to temperatures higher than 40 degrees C. These findings may help in understanding the survival mechanism of dessert mosses under heat shock stress which will be helpful for the artificial reconstruction of BSCs.

  20. The effects of drying following heat shock exposure of the desert moss Syntrichia caninervis

    International Nuclear Information System (INIS)

    Xu Shujun; Liu Chunjiang; Jiang Pingan; Cai Weimin; Wang Yan

    2009-01-01

    Desert mosses are components of biological soil crusts (BSCs) and their ecological functions make assessment and protection of these mosses a high-ranking management priority in desert regions. Drying is thought to be useful for desert mosses surviving heat shock. In this study, we investigated the role of drying by monitoring the responses of physiological characters and asexual reproduction in the typical desert moss Syntrichia caninervis. Heat significantly decreased chlorophyll content and weakened rapid recovery of photochemical activity, and increased carotenoid content and membrane permeability. Lethal temperatures significantly destroyed shoot regeneration potential. In comparison with heat alone, drying significantly increased protonema emergence time and depressed protonema emergence area. Drying combined with heat accelerated water loss, followed by a decrease of photosynthetic activity. Drying had different influences on membrane permeability at different temperatures. When moss leaves were subjected to a combined stress of drying and heat shock, photosynthesis was maintained mainly due to the effects of drying on physiological activity although the cellular morphological integrity was affected. Drying caused opposing effects on moss physiological and reproductive characteristics. On the one hand, drying caused a positive synergistic effect with heat shock when the temperature was below 40 deg. C. On the other hand, drying showed antagonism with heat shock when the moss was subjected to temperatures higher than 40 deg. C. These findings may help in understanding the survival mechanism of dessert mosses under heat shock stress which will be helpful for the artificial reconstruction of BSCs

  1. Pacman dysplasia: a lethal skeletal dysplasia with variable radiographic features

    Energy Technology Data Exchange (ETDEWEB)

    Miller, S.F. [Dept. of Radiology, Children' s Hospital of the King' s Daughters, Norfolk (United States); Proud, V.K. [Dept. of Genetics, Children' s Hospital of the King' s Daughters, Norfolk (United States); Werner, A.L. [Dept. of Pathology, Children' s Hospital of the King' s Daughters, Norfolk (United States); Field, F.M.; Wilcox, W.F.; Lachman, R.S.; Rimoin, D.L. [International Skeletal Dysplasia Registry, Cedars-Sinai Medical Center, Los Angeles (United States)

    2003-04-01

    Background: Punctate or stippled cartilaginous calcifications are associated with many conditions, including chromosomal, infectious, endocrine, and teratogenic etiologies. Some of these conditions are clinically mild, while others are lethal. Accurate diagnosis can prove instrumental in clinical management and in genetic counseling. Objective: To describe the diagnostic radiographic features seen in Pacman dysplasia, a distinct autosomal recessive, lethal skeletal dysplasia. Materials and methods: We present the fourth reported case of Pacman dysplasia and compare the findings seen in our patient with the three previously described patients. Results: Invariable and variable radiographic findings were seen in all four cases of histologically proven Pacman dysplasia. Conclusion: Pacman dysplasia presents both constant and variable diagnostic radiographic features. (orig.)

  2. Neonatal lethal dwarfism with distinct skeletal malformations - a separate entity?

    Energy Technology Data Exchange (ETDEWEB)

    Rosendahl, K.; Maurseth, K.; Olsen, Oe.E. [Dept. of Paediatric Radiology, Haukeland University Hospital, Bergen (Norway); Halvorsen, O.J. [Dept. of Pathology, Haukeland University Hospital, Bergen (Norway); Gjelland, K. [Dept. of Gynaecology, Haukeland University Hospital, Bergen (Norway); Engebretsen, L. [Dept. of Genetics, Haukeland University Hospital, Bergen (Norway)

    2001-09-01

    We describe a case of neonatal lethal dwarfism characterised by short trunk, short, stick-like tubular bones, deficient ossification of the axial skeleton and broad, sclerotic horizontal ribs. Two similar cases have previously been reported as examples of the Neu-Laxova syndrome. However, the radiological findings of the Neu-Laxova syndrome, as reported in 16 out of 40 documented cases, show a heterogeneous pattern of minor features, which differ distinctively from those found in the previous two cases and by us. A literature research did not reveal similar cases, and we therefore suggest that our case, together with the two previous cases, may represent a new distinctive form of neonatal lethal dwarfism. (orig.)

  3. Neonatal lethal dwarfism with distinct skeletal malformations - a separate entity?

    International Nuclear Information System (INIS)

    Rosendahl, K.; Maurseth, K.; Olsen, Oe.E.; Halvorsen, O.J.; Gjelland, K.; Engebretsen, L.

    2001-01-01

    We describe a case of neonatal lethal dwarfism characterised by short trunk, short, stick-like tubular bones, deficient ossification of the axial skeleton and broad, sclerotic horizontal ribs. Two similar cases have previously been reported as examples of the Neu-Laxova syndrome. However, the radiological findings of the Neu-Laxova syndrome, as reported in 16 out of 40 documented cases, show a heterogeneous pattern of minor features, which differ distinctively from those found in the previous two cases and by us. A literature research did not reveal similar cases, and we therefore suggest that our case, together with the two previous cases, may represent a new distinctive form of neonatal lethal dwarfism. (orig.)

  4. Hematologic syndrome in man modeled from mammalian lethality

    International Nuclear Information System (INIS)

    Jones, T.D.

    1981-01-01

    Data on acute radiation lethality due to failure of the hematologic system in rats, mice, dogs, swine, monkeys and man are analyzed. Based on the available data, the mortality incidences for 1-100% levels can be computed directly if one has only an estimate of the dose lethal to 50% of the population (LD 50 ) for the mammalian strain and radiation environment of interest. The sole restriction is that the dose profile to the marrow be moderately uniform. If an LD 50 for any exposure situation has been measured, then one can readily scale to any desired situation through implicit-biological and empirical-physical relationships. The LD 50 for man, exposed to an isotropic cloud of photons, and knowledge of the bone-marrow dose profiles readily permit evaluation of the model for other levels of human mortality from different irradiating particles, partial body irradiation and spatially dependent and/or mixed radiation environments. (author)

  5. Chemical and radiation induced late dominant lethal effects in mice

    International Nuclear Information System (INIS)

    Favor, J.; Crenshaw, J.W. Jr.; Soares, E.R.

    1978-01-01

    Although theoretically expected, experimental data to date have not shown dominant lethal expression to occur throughout the developmental period. Specifically, late post-implantation effects have not been demonstrated. The authors routinely use an experimental technique in which parental females mated to mutagenically treated males are allowed to give birth and wean their litter, and their uterine horns are then inspected for uterine scars indicative of live and dead embryos. In a number of experiments in which males were mutagenically treated with either chemicals or X-irradiation, a discrepancy was observed between the number of live embryos as determined by the scar technique and the number of live observed at birth, suggesting the possibility of embryonic losses at a late stage in development. Initial analyses showed that mutagenic treatment increased the percentage of these late losses. These differences were statistically significant in 2 of 3 analyses. Factors affecting statistical significance and an understanding of dominant lethal mutations are discussed. (Auth.)

  6. An improved brine shrimp larvae lethality microwell test method.

    Science.gov (United States)

    Zhang, Yi; Mu, Jun; Han, Jinyuan; Gu, Xiaojie

    2012-01-01

    This article described an improved brine shrimp larvae lethality microwell test method. A simply designed connecting vessel with alternative photoperiod was used to culture and collect high yield of active Artemia parthenogenetica nauplii for brine shrimp larvae lethality microwell test. Using this method, pure A. parthenogenetica nauplii suspension was easily cultured and harvested with high density about 100-150 larvae per milliliter and the natural mortality was reduced to near zero by elimination of unnecessary artificial disturbance. And its sensitivity was validated by determination of LC(50)-24 h of different reference toxicants including five antitumor agents, two pesticides, three organic pollutants, and four heavy metals salts, most of which exhibited LC(50)-24 h between 0.07 and 58.43 mg/L except for bleomycin and mitomycin C with LC(50)-24 h over 300 mg/L.

  7. Dominant lethals following administration of tritium (THO) to rat males

    International Nuclear Information System (INIS)

    Yagova, A.; Baev, I.; Bajrakova, A.

    1976-01-01

    Adult rat males were given a single intraperitoneal tritium (THO) injection at 0,01 or 0,001 mCi/g body weight (1/100 or 1/1000 of LDsub(50/30), respectively). Twelve days after treatment each male was mated to 3-5 intact females, and the latter were replaced by fresh ones every 12 following days over a 120-day period. Mated females were killed to score conceptions, corpora lutea, and live and dead embryos. Estimations were made of F 1 prenatal death rate (according to Bateman, 1958) and the frequency of induction of dominant lethal mutations (according to Roehrborn, 1970). The results observed indicated paternal exposure to tritium (THO) to produce dominant lethals both in pre- and post-meiotic germ cells in the rat. The extent of the genetic damage studied was found to depend on the amount of activity administered as well as on the time interval between treatment and conception. (author)

  8. Shock parameter calculations at weak interplanetary shock waves

    Directory of Open Access Journals (Sweden)

    J. M. Gloag

    2005-02-01

    Full Text Available A large set of interplanetary shock waves observed using the Ulysses spacecraft is analysed in order to determine their local parameters. For the first time a detailed analysis is extended to the thermodynamic properties of a large number of events. The intention is to relate the shock parameters to the requirements set by MHD shock theory. A uniform approach is adopted in the selection of up and downstream regions for this analysis and applied to all the shock waves. Initially, the general case of a 3 component adiabatic plasma is considered. However, the calculation of magnetosonic and Alfvénic Mach numbers and the ratio of downstream to upstream entropy produce some unexpected results. In some cases there is no clear increase in entropy across the shock and also the magnetosonic Mach number can be less than 1. It is found that a more discerning use of data along with an empirical value for the polytropic index can raise the distribution of downstream to upstream entropy ratios to a more acceptable level. However, it is also realised that many of these shocks are at the very weakest end of the spectrum and associated phenomena may also contribute to the explanation of these results.

  9. Quasilinear simulations of interplanetary shocks and Earth's bow shock

    Science.gov (United States)

    Afanasiev, Alexandr; Battarbee, Markus; Ganse, Urs; Vainio, Rami; Palmroth, Minna; Pfau-Kempf, Yann; Hoilijoki, Sanni; von Alfthan, Sebastian

    2016-04-01

    We have developed a new self-consistent Monte Carlo simulation model for particle acceleration in shocks. The model includes a prescribed large-scale magnetic field and plasma density, temperature and velocity profiles and a self-consistently computed incompressible ULF foreshock under the quasilinear approximation. Unlike previous analytical treatments, our model is time dependent and takes full account of the anisotropic particle distributions and scattering in the wave-particle interaction process. We apply the model to the problem of particle acceleration at traveling interplanetary (IP) shocks and Earth's bow shock and compare the results with hybrid-Vlasov simulations and spacecraft observations. A qualitative agreement in terms of spectral shape of the magnetic fluctuations and the polarization of the unstable mode is found between the models and the observations. We will quantify the differences of the models and explore the region of validity of the quasilinear approach in terms of shock parameters. We will also compare the modeled IP shocks and the bow shock, identifying the similarities and differences in the spectrum of accelerated particles and waves in these scenarios. The work has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 637324 (HESPERIA). The Academy of Finland is thanked for financial support. We acknowledge the computational resources provided by CSC - IT Centre for Science Ltd., Espoo.

  10. Diaphragmless shock wave generators for industrial applications of shock waves

    Science.gov (United States)

    Hariharan, M. S.; Janardhanraj, S.; Saravanan, S.; Jagadeesh, G.

    2011-06-01

    The prime focus of this study is to design a 50 mm internal diameter diaphragmless shock tube that can be used in an industrial facility for repeated loading of shock waves. The instantaneous rise in pressure and temperature of a medium can be used in a variety of industrial applications. We designed, fabricated and tested three different shock wave generators of which one system employs a highly elastic rubber membrane and the other systems use a fast acting pneumatic valve instead of conventional metal diaphragms. The valve opening speed is obtained with the help of a high speed camera. For shock generation systems with a pneumatic cylinder, it ranges from 0.325 to 1.15 m/s while it is around 8.3 m/s for the rubber membrane. Experiments are conducted using the three diaphragmless systems and the results obtained are analyzed carefully to obtain a relation between the opening speed of the valve and the amount of gas that is actually utilized in the generation of the shock wave for each system. The rubber membrane is not suitable for industrial applications because it needs to be replaced regularly and cannot withstand high driver pressures. The maximum shock Mach number obtained using the new diaphragmless system that uses the pneumatic valve is 2.125 ± 0.2%. This system shows much promise for automation in an industrial environment.

  11. Non-Lethal Weaponry: A Framework for Future Integration

    Science.gov (United States)

    1998-04-01

    community, but was widely popularized by John Naisbitt in his 1982 work, Megatrends . In short, it asserts that much may be learned about a dynamic, but...Notes 1 John Naisbitt, Megatrends : Ten New Directions Transforming Our Lives (New York, NY: Warner Books, Inc., 1982), 3-5. 2 Robert J. Bunker...lethals by opponents of biological and chemical weapons. The use of chemical agents…is seen as a Trojan Horse to circumvent the Chemical Weapons

  12. Genome Replikin Count Predicts Increased Infectivity/Lethality of Viruses

    OpenAIRE

    Samuel Bogoch; Elenore S. Bogoch

    2012-01-01

    The genomes of all groups of viruses whose sequences are listed on Pubmed, specimens since 1918, analyzed by a software from Bioradar UK Ltd., contain Replikins which range in concentration from a Replikin Count (number of Replikins per 100 amino acids) of less than 1 to 30 (see accompanying communications for higher Counts in tuberculosis, malaria, and cancer, associated with higher lethality). Counts of less than 4.0 were found in ‘resting’ virus states; Counts greater than 4....

  13. Spondyloepiphyseal dysplasia congenita. A cause of lethal neonatal dwarfism

    Energy Technology Data Exchange (ETDEWEB)

    Macpherson, R.I.; Wood, B.P.

    1980-07-01

    Spondyloepiphyseal dysplasia congenita is a form of primarily short trunk dwarfism, that is manifest at birth but generally has not been regarded as a cause of lethal neonatal dwarfism. Seven neonates with severe dwarfism are presented. The first survived the newborn period, but the other six were early neonatal deaths. All displayed the clinical and radiologic features of spondyloepiphyseal dysplasia congenita. The striking similarities between spondyloepiphyseal dysplasia congenita and achondrogenesis type 2 are discussed.

  14. Torrance type of lethal neonatal short-limbed platyspondylic dwarfism

    International Nuclear Information System (INIS)

    Kaibara, N.; Yokoyama, K.; Nakano, H.

    1983-01-01

    A rare case of lethal neonatal short-limbed platyspondylic dwarfism is described. Roentgenographic features of this case, distinctly different from those of the classical thanatophoric dysplasia, are indistinguishable from the other three types of short-limbed platyspondylic dwarfism. Histologic features of the cartilage in this case are not very different from those of the Torrance type, but the presence of focal disruption of column formation in this case suggests a wider spectrum for this entity. (orig.)

  15. Torrance type of lethal neonatal short-limbed platyspondylic dwarfism

    Energy Technology Data Exchange (ETDEWEB)

    Kaibara, N.; Yokoyama, K.; Nakano, H.

    1983-06-01

    A rare case of lethal neonatal short-limbed platyspondylic dwarfism is described. Roentgenographic features of this case, distinctly different from those of the classical thanatophoric dysplasia, are indistinguishable from the other three types of short-limbed platyspondylic dwarfism. Histologic features of the cartilage in this case are not very different from those of the Torrance type, but the presence of focal disruption of column formation in this case suggests a wider spectrum for this entity.

  16. First diagnosed lethal case of lyssavirus infection in Primorsky krai

    OpenAIRE

    Leonova, G.; Chentsova, I.; Petukhova, S.; Somova, L.; Belikov, S.; Kondratov, I.; Kryilova, N.; Plekhova, N.; Pavlenko, E.; Romanova, E.; Matsak, V.; Smirnov, G.; Novikov, D.

    2010-01-01

    The paper provides data of comprehensive study of lethal case of lyssavirus infection first diagnosed in Yakovlevsky municipal district in Primorsky Krai. The data of epidemiologic analysis (contact with a rattle mouse), clinical picture and results of virologic, morphological and molecular genetic tests allow attributing this case to lyssavirus infection. This is the first diagnosed case of lyssavirus infection in the Siberia and Far East.

  17. Transplantation of bone marrow cells into lethally irradiated mice

    International Nuclear Information System (INIS)

    Viktora, L.; Hermanova, E.

    1978-01-01

    Morphological changes were studied of megakaryocytes in the bone marrow and spleen of lethally irradiated mice (0.2 C/kg) after transplantation of living bone marrow cells. It was observed that functional trombopoietic megakaryocytes occur from day 15 after transplantation and that functional active megakaryocytes predominate in bone marrow and spleen from day 20. In addition, other types of cells, primarily granulocytes, were detected in some megakaryocytes. (author)

  18. Shock wave dynamics derivatives and related topics

    CERN Document Server

    Emanuel, George

    2012-01-01

    "...this monograph develops an esoteric niche within shock wave theory. …treats shock waves from an analytical approach assuming perfect gas. Emanuel has made significant contributions to the theory of shock waves and has selected a number of topics that reflect those contributions."-Shock Waves, 2013.

  19. Temperature shock, injury and transient sensitivity to nisin in Gram negatives.

    Science.gov (United States)

    Boziaris, I S; Adams, M R

    2001-10-01

    The effect of thermal stresses on survival, injury and nisin sensitivity was investigated in Salmonella Enteritidis PT4, PT7 and Pseudomonas aeruginosa. Heating at 55 degrees C, rapid chilling to 0.5 degrees C or freezing at -20 degrees C produced transient sensitivity to nisin. Cells were only sensitive if nisin was present during stress. Resistance recovered rapidly afterwards, though some cells displayed residual injury. Injury was assessed by SDS sensitivity, hydrophobicity changes, lipopolysaccharide release and NPN uptake. LPS release and hydrophobicity were not always associated with transient nisin sensitivity. Uptake of NPN correlated better but persisted longer after treatment. Thermal shocks produce transient injury to the outer membrane, allowing nisin access. After treatment, the permeability barrier is rapidly restored by a process apparently involving reorganization rather than biosynthetic repair. Inclusion of nisin during food treatments that impose sub-lethal stress on Gram negatives could increase process lethality, enhancing microbiological safety and stability.

  20. Lethal mutagenesis: targeting the mutator phenotype in cancer.

    Science.gov (United States)

    Fox, Edward J; Loeb, Lawrence A

    2010-10-01

    The evolution of cancer and RNA viruses share many similarities. Both exploit high levels of genotypic diversity to enable extensive phenotypic plasticity and thereby facilitate rapid adaptation. In order to accumulate large numbers of mutations, we have proposed that cancers express a mutator phenotype. Similar to cancer cells, many viral populations, by replicating their genomes with low fidelity, carry a substantial mutational load. As high levels of mutation are potentially deleterious, the viral mutation frequency is thresholded at a level below which viral populations equilibrate in a traditional mutation-selection balance, and above which the population is no longer viable, i.e., the population undergoes an error catastrophe. Because their mutation frequencies are fine-tuned just below this error threshold, viral populations are susceptible to further increases in mutational load and, recently this phenomenon has been exploited therapeutically by a concept that has been termed lethal mutagenesis. Here we review the application of lethal mutagenesis to the treatment of HIV and discuss how lethal mutagenesis may represent a novel therapeutic approach for the treatment of solid cancers. Copyright © 2010 Elsevier Ltd. All rights reserved.

  1. Nonlinearity, Conservation Law and Shocks

    Indian Academy of Sciences (India)

    Almost all natural phenomena, and social and economic changes, .... reference moving with velocity c also by the same symbol x and ... abstract as can be seen from the publication of the book Shock Waves and Reaction Diffusion Equation.

  2. Shock Thermodynamic Applied Research Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Shock Thermodynamic Applied Research Facility (STAR) facility, within Sandia’s Solid Dynamic Physics Department, is one of a few institutions in the world with a...

  3. Target design for shock ignition

    International Nuclear Information System (INIS)

    Schurtz, G; Ribeyre, X; Lafon, M

    2010-01-01

    The conventional approach of laser driven inertial fusion involves the implosion of cryogenic shells of deuterium-tritium ice. At sufficiently high implosion velocities, the fuel ignites by itself from a central hot spot. In order to reduce the risks of hydrodynamic instabilities inherent to large implosion velocities, it was proposed to compress the fuel at low velocity, and ignite the compressed fuel by means of a convergent shock wave driven by an intense spike at the end of the laser pulse. This scheme, known as shock ignition, reduces the risks of shell break-up during the acceleration phase, but it may be impeded by a low coupling efficiency of the laser pulse with plasma at high intensities. This work provides a relationship between the implosion velocity and the laser intensity required to ignite the target by a shock. The operating domain of shock ignition at different energies is described.

  4. Undercuts by Laser Shock Forming

    International Nuclear Information System (INIS)

    Wielage, Hanna; Vollertsen, Frank

    2011-01-01

    In laser shock forming TEA-CO 2 -laser induced shock waves are used to form metal foils, such as aluminum or copper. The process utilizes an initiated plasma shock wave on the target surface, which leads to a forming of the foil. A challenge in forming technologies is the manufacturing of undercuts. By conventional forming methods these special forms are not feasible. In this article, it is presented that undercuts in the micro range can be produced by laser shock deep drawing. Different drawing die diameters, drawing die depths and the material aluminum in the thicknesses 20 and 50 μm were investigated. It will be presented that smaller die diameters facilitate undercuts compared to bigger die diameters. The phenomena can be explained by Barlow's formula. Furthermore, it is shown which maximum undercut depth at different die diameters can be reached. To this end, cross-sections of the different parameter combinations are displayed.

  5. Electric Shock Injuries in Children

    Science.gov (United States)

    ... Issues Listen Español Text Size Email Print Share Electric Shock Injuries in Children Page Content ​When the ... comes into direct contact with a source of electricity, the current passes through it, producing what's called ...

  6. Relativistic shocks and particle acceleration

    International Nuclear Information System (INIS)

    Heavens, A.F.

    1988-01-01

    In this paper, we investigate the fluid dynamics of relativistic shock waves, and use the results to calculate the spectral index of particles accelerated by the Fermi process in such shocks. We have calculated the distributions of Fermi-accelerated particles at shocks propagating into cold proton-electron plasma and also cold electron-positron plasma. We have considered two different power spectra for the scattering waves, and find, in contrast to the non-relativistic case, that the spectral index of the accelerated particles depends on the wave power spectrum. On the assumption of thermal equilibrium both upstream and downstream, we present some useful fits for the compression ratio of shocks propagating at arbitrary speeds into gas of any temperature. (author)

  7. Shock wave interaction with turbulence: Pseudospectral simulations

    International Nuclear Information System (INIS)

    Buckingham, A.C.

    1986-01-01

    Shock waves amplify pre-existing turbulence. Shock tube and shock wave boundary layer interaction experiments provide qualitative confirmation. However, shock pressure, temperature, and rapid transit complicate direct measurement. Computational simulations supplement the experimental data base and help isolate the mechanisms responsible. Simulations and experiments, particularly under reflected shock wave conditions, significantly influence material mixing. In these pseudospectral Navier-Stokes simulations the shock wave is treated as either a moving (tracked or fitted) domain boundary. The simulations assist development of code mix models. Shock Mach number and pre-existing turbulence intensity initially emerge as key parameters. 20 refs., 8 figs

  8. The Efficacy of Cognitive Shock

    Science.gov (United States)

    2015-05-21

    way, causing dissonance or cognitive conflict, so that the mental model has to be ‘accommodated’ to the new data. Categories and knowledge have to...The Efficacy of Cognitive Shock A Monograph by MAJ Anthony L. Marston United States Army School of Advanced Military Studies...DATES COVERED (From - To) JUN 2014 – MAY 2015 4. TITLE AND SUBTITLE The Efficacy of Cognitive Shock 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c

  9. Pressurized Thermal Shock, Pts

    International Nuclear Information System (INIS)

    Boyd, C.

    2008-01-01

    Pressurized Thermal Shock (Pts) refers to a condition that challenges the integrity of the reactor pressure vessel. The root cause of this problem is the radiation embrittlement of the reactor vessel. This embrittlement leads to an increase in the reference temperature for nil ductility transition (RTNDT). RTNDT can increase to the point where the reactor vessel material can loose fracture toughness during overcooling events. The analysis of the risk of having a Pts for a specific plant is a multi-disciplinary problem involving probabilistic risk analysis (PRA), thermal-hydraulic analysis, and ultimately a structural and fracture analysis of the vessel wall. The PRA effort involves the postulation of overcooling events and ultimately leads to an integrated risk analysis. The thermal-hydraulic effort involves the difficult task of predicting the system behavior during a postulated overcooling scenario with a special emphasis on predicting the thermal and mechanic loadings on the reactor pressure vessel wall. The structural and fracture analysis of the reactor vessel wall relies on the thermal-hydraulic conditions as boundary conditions. The US experience has indicated that medium and large diameter primary system breaks dominate the risk of Pts along with scenarios that involve a stuck open valve (and associated system cooldown) that recloses resulting in system re-pressurization while the vessel wall is cool.

  10. Sepsis and septic shock

    Science.gov (United States)

    Hotchkiss, Richard S.; Moldawer, Lyle L.; Opal, Steven M.; Reinhart, Konrad; Turnbull, Isaiah R.; Vincent, Jean-Louis

    2017-01-01

    For more than two decades, sepsis was defined as a microbial infection that produces fever (or hypothermia), tachycardia, tachypnoea and blood leukocyte changes. Sepsis is now increasingly being considered a dysregulated systemic inflammatory and immune response to microbial invasion that produces organ injury for which mortality rates are declining to 15–25%. Septic shock remains defined as sepsis with hyperlactataemia and concurrent hypotension requiring vasopressor therapy, with in-hospital mortality rates approaching 30–50%. With earlier recognition and more compliance to best practices, sepsis has become less of an immediate life-threatening disorder and more of a long-term chronic critical illness, often associated with prolonged inflammation, immune suppression, organ injury and lean tissue wasting. Furthermore, patients who survive sepsis have continuing risk of mortality after discharge, as well as long-term cognitive and functional deficits. Earlier recognition and improved implementation of best practices have reduced in-hospital mortality, but results from the use of immunomodulatory agents to date have been disappointing. Similarly, no biomarker can definitely diagnose sepsis or predict its clinical outcome. Because of its complexity, improvements in sepsis outcomes are likely to continue to be slow and incremental. PMID:28117397

  11. Ubiquitous overexpression of a transgene encoding the extracellular portion of the Drosophila roughest-irregular chiasm C protein induces early embryonic lethality.

    Science.gov (United States)

    Moda, L; Machado, R C; Ramos, R G

    2000-09-01

    The cell adhesion molecule Rst-irreC is a transmembrane glycoprotein of the immunoglobulin superfamily involved in several important developmental processes in Drosophila, including axonal pathfinding in the optic lobe and programmed cell death and pigment cell differentiation in the pupal retina. As an initial step towards the "in vivo" functional analysis of this protein we have generated transgenic fly stocks carrying a truncated cDNA construct encoding only the extracellular domain of Rst-IrreC under the transcriptional control of the heat shock inducible promoter hsp70. We show that heat-shocking embryos bearing the transgene during the first 8hs of development lead to a 3-4 fold reduction in their viability compared to wild type controls. The embryonic lethality can already be produced by applying the heat pulse in the first 3hs of embryonic development, does not seem to be suppressed in the absence of wildtype product and is progressively reduced as the heat treatment is applied later in embryogenesis. These results are compatible with the hypothesis of the lethal phenotype being primarily due to heterophilic interactions between Rst-IrreC extracellular domain and an yet unknown ligand.

  12. Focusing of Shear Shock Waves

    Science.gov (United States)

    Giammarinaro, Bruno; Espíndola, David; Coulouvrat, François; Pinton, Gianmarco

    2018-01-01

    Focusing is a ubiquitous way to transform waves. Recently, a new type of shock wave has been observed experimentally with high-frame-rate ultrasound: shear shock waves in soft solids. These strongly nonlinear waves are characterized by a high Mach number, because the shear wave velocity is much slower, by 3 orders of magnitude, than the longitudinal wave velocity. Furthermore, these waves have a unique cubic nonlinearity which generates only odd harmonics. Unlike longitudinal waves for which only compressional shocks are possible, shear waves exhibit cubic nonlinearities which can generate positive and negative shocks. Here we present the experimental observation of shear shock wave focusing, generated by the vertical motion of a solid cylinder section embedded in a soft gelatin-graphite phantom to induce linearly vertically polarized motion. Raw ultrasound data from high-frame-rate (7692 images per second) acquisitions in combination with algorithms that are tuned to detect small displacements (approximately 1 μ m ) are used to generate quantitative movies of gel motion. The features of shear shock wave focusing are analyzed by comparing experimental observations with numerical simulations of a retarded-time elastodynamic equation with cubic nonlinearities and empirical attenuation laws for soft solids.

  13. Shock compression of synthetic opal

    International Nuclear Information System (INIS)

    Inoue, A; Okuno, M; Okudera, H; Mashimo, T; Omurzak, E; Katayama, S; Koyano, M

    2010-01-01

    Structural change of synthetic opal by shock-wave compression up to 38.1 GPa has been investigated by using SEM, X-ray diffraction method (XRD), Infrared (IR) and Raman spectroscopies. Obtained information may indicate that the dehydration and polymerization of surface silanole due to high shock and residual temperature are very important factors in the structural evolution of synthetic opal by shock compression. Synthetic opal loses opalescence by 10.9 and 18.4 GPa of shock pressures. At 18.4 GPa, dehydration and polymerization of surface silanole and transformation of network structure may occur simultaneously. The 4-membered ring of TO 4 tetrahedrons in as synthetic opal may be relaxed to larger ring such as 6-membered ring by high residual temperature. Therefore, the residual temperature may be significantly high at even 18.4 GPa of shock compression. At 23.9 GPa, opal sample recovered the opalescence. Origin of this opalescence may be its layer structure by shock compression. Finally, sample fuse by very high residual temperature at 38.1 GPa and the structure closes to that of fused SiO 2 glass. However, internal silanole groups still remain even at 38.1 GPa.

  14. Computations of slowly moving shocks

    International Nuclear Information System (INIS)

    Karni, S.; Canic, S.

    1997-01-01

    Computations of slowly moving shocks by shock capturing schemes may generate oscillations are generated already by first-order schemes, but become more pronounced in higher-order schemes which seem to exhibit different behaviors: (i) the first-order upwind (UW) scheme which generates strong oscillations and (ii) the Lax-Friedrichs scheme which appears not to generate any disturbances at all. A key observation is that in the UW case, the numerical viscosity in the shock family vanishes inside the slow shock layer. Simple scaling arguments show the third-order effects on the solution may no longer be neglected. We derive the third-order modified equation for the UW scheme and regard the oscillatory solution as a traveling wave solution of the parabolic modified equation for the perturbation. We then look at the governing equation for the perturbation, which points to a plausible mechanism by which postshock oscillations are generated. It contains a third-order source term that becomes significant inside the shock layer, and a nonlinear coupling term which projects the perturbation on all characteristic fields, including those not associated with the shock family. 5 refs., 8 figs

  15. Shock compression of synthetic opal

    Science.gov (United States)

    Inoue, A.; Okuno, M.; Okudera, H.; Mashimo, T.; Omurzak, E.; Katayama, S.; Koyano, M.

    2010-03-01

    Structural change of synthetic opal by shock-wave compression up to 38.1 GPa has been investigated by using SEM, X-ray diffraction method (XRD), Infrared (IR) and Raman spectroscopies. Obtained information may indicate that the dehydration and polymerization of surface silanole due to high shock and residual temperature are very important factors in the structural evolution of synthetic opal by shock compression. Synthetic opal loses opalescence by 10.9 and 18.4 GPa of shock pressures. At 18.4 GPa, dehydration and polymerization of surface silanole and transformation of network structure may occur simultaneously. The 4-membered ring of TO4 tetrahedrons in as synthetic opal may be relaxed to larger ring such as 6-membered ring by high residual temperature. Therefore, the residual temperature may be significantly high at even 18.4 GPa of shock compression. At 23.9 GPa, opal sample recovered the opalescence. Origin of this opalescence may be its layer structure by shock compression. Finally, sample fuse by very high residual temperature at 38.1 GPa and the structure closes to that of fused SiO2 glass. However, internal silanole groups still remain even at 38.1 GPa.

  16. Shock compression of synthetic opal

    Energy Technology Data Exchange (ETDEWEB)

    Inoue, A; Okuno, M; Okudera, H [Department of Earth Sciences, Kanazawa University Kanazawa, Ishikawa, 920-1192 (Japan); Mashimo, T; Omurzak, E [Shock Wave and Condensed Matter Research Center, Kumamoto University, Kumamoto, 860-8555 (Japan); Katayama, S; Koyano, M, E-mail: okuno@kenroku.kanazawa-u.ac.j [JAIST, Nomi, Ishikawa, 923-1297 (Japan)

    2010-03-01

    Structural change of synthetic opal by shock-wave compression up to 38.1 GPa has been investigated by using SEM, X-ray diffraction method (XRD), Infrared (IR) and Raman spectroscopies. Obtained information may indicate that the dehydration and polymerization of surface silanole due to high shock and residual temperature are very important factors in the structural evolution of synthetic opal by shock compression. Synthetic opal loses opalescence by 10.9 and 18.4 GPa of shock pressures. At 18.4 GPa, dehydration and polymerization of surface silanole and transformation of network structure may occur simultaneously. The 4-membered ring of TO{sub 4} tetrahedrons in as synthetic opal may be relaxed to larger ring such as 6-membered ring by high residual temperature. Therefore, the residual temperature may be significantly high at even 18.4 GPa of shock compression. At 23.9 GPa, opal sample recovered the opalescence. Origin of this opalescence may be its layer structure by shock compression. Finally, sample fuse by very high residual temperature at 38.1 GPa and the structure closes to that of fused SiO{sub 2} glass. However, internal silanole groups still remain even at 38.1 GPa.

  17. Electromagnetically driven radiative shocks and their measurements

    International Nuclear Information System (INIS)

    Kondo, K.; Watanabe, M.; Nakajima, M.; Kawamura, T.; Horioka, K.

    2005-01-01

    Experimental results on a generation of strong shocks in a compact pulse power device are reported. The characteristics of strong shocks are different from hydrodynamical shocks' because they depend on not only collisions but radiation processes. Radiative shocks are relevant to high energy density phenomena such as the explosions of supernovae. When initial pressure is lower than about 50 mtorr, an interesting structure is confirmed at the shock front, which might indicate a phenomenon proceeded by the radiative process. (author)

  18. Lethal and Sub-lethal Effects of Four Insecticides on the Aphidophagous Coccinellid Adalia bipunctata (Coleoptera: Coccinellidae).

    Science.gov (United States)

    Depalo, Laura; Lanzoni, Alberto; Masetti, Antonio; Pasqualini, Edison; Burgio, Giovanni

    2017-12-05

    Conventional insecticide assays, which measure the effects of insecticide exposure on short-term mortality, overlook important traits, including persistence of toxicity or sub-lethal effects. Therefore, such approaches are especially inadequate for prediction of the overall impact of insecticides on beneficial arthropods. In this study, the side effects of four modern insecticides (chlorantraniliprole, emamectin benzoate, spinosad, and spirotetramat) on Adalia bipunctata (L.) (Coleoptera: Coccinellidae) were evaluated under laboratory conditions by exposition on treated potted plants. In addition to investigation of acute toxicity and persistence of harmful activity in both larvae and adults of A. bipunctata, demographic parameters were evaluated, to provide a comprehensive picture of the nontarget effects of these products. Field doses of the four insecticides caused detrimental effects to A. bipunctata; but in different ways. Overall, spinosad showed the best toxicological profile among the products tested. Emamectin benzoate could be considered a low-risk insecticide, but had high persistence. Chlorantraniliprole exhibited lethal effects on early instar larvae and adults, along with a long-lasting activity, instead spirotetramat showed a low impact on larval and adult mortality and can be considered a short-lived insecticide. However, demographic analysis demonstrated that chlorantraniliprole and spirotetramat caused sub-lethal effects. Our findings highlight that sole assessment of mortality can lead to underestimation of the full impact of pesticides on nontarget insects. Demographic analysis was demonstrated to be a sensitive method for detection of the sub-lethal effects of insecticides on A. bipunctata, and this approach should be considered for evaluation of insecticide selectivity. © The Author(s) 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  19. Reprodaetion of an animal model of multiple intestinal injuries mimicking "lethal triad" caused by severe penetrating abdominal trauma

    Directory of Open Access Journals (Sweden)

    Peng-fei WANG

    2011-03-01

    Full Text Available Objective To reproduce an animal model of multi-intestinal injuries with "lethal triad" characterized by low body temperature,acidosis and coagulopathy.Methods Six female domestic outbred pigs were anesthetized,and the carotid artery and jugular vein were cannulated for monitoring the blood pressure and heart rate and for infusion of fluid.The animals were shot with a gun to create a severe penetrating abdominal trauma.Immediately after the shooting,50% of total blood volume(35ml/kg hemorrhage was drawn from the carotid artery in 20min.After a 40min shock period,4h of pre-hospital phase was mimicked by normal saline(NS resuscitation to maintain systolic blood pressure(SBP > 80mmHg or mean arterial pressure(MAP > 60mmHg.When SBP > 80mmHg or MAP > 60mmHg,no fluid infusion or additional bleeding was given.Hemodynamic parameters were recorded,and pathology of myocardium,lung,small intestine and liver was observed.Results There were multiple intestinal perforations(8-10 site injuries/pig leading to intra-abdominal contamination,mesenteric injury(1-2 site injuries/pig resulted in partial intestinal ischemia and intra-abdominal hemorrhage,and no large colon and mesenteric vascular injury.One pig died before the completion of the model establishment(at the end of pre-hospital resuscitation.The typical symptoms of trauma-induced hemorrhagic shock were observed in survival animals.Low temperature(33.3±0.5℃,acidosis(pH=7.242±0.064,and coagulopathy(protrombin time and activated partial thromboplasting time prolonged were observed after pre-hospital resuscitation.Pathology showed that myocardium,lung,small intestine and liver were severely injured.Conclusions A new model,simulating three stages of "traumatic hemorrhagic shock,pre-hospital recovery and hospital treatment" and inducing the "lethal triad" accompanied with abdominal pollution,has been successfully established.This model has good stability and high reproducibility.The survival animals can be

  20. Left ventricular calcification following postpartum toxic shock syndrome

    Directory of Open Access Journals (Sweden)

    Stella C Pak

    2018-01-01

    Full Text Available Toxic shock syndrome (TSS is a rare but lethal clinical event that can occur during the postpartum period. Early recognition and intervention is critical to improve patient outcomes. This is a case of TSS complicated by cardiac arrest and left ventricular calcification. This is a case report of streptococcal TSS in a 29-year-old female in the postpartum period who presented with fever, abdominal distension, and a purpuric rash. Her hospital course was characterized by multiple organ failure, including respiratory distress syndrome, liver failure, renal failure, and coagulopathy. She was found to have acute compartment syndrome, which resulted in a below-the-knee amputation. She deteriorated further after experiencing cardiac arrest and the development of hypoxic-ischemic encephalopathy with hemorrhagic transformation. A computed tomography scan of the chest revealed evidence of dystrophic myocardial calcification in the left ventricle. She improved clinically but remained ventilator dependent upon discharge to an extended acute care facility. Sepsis-induced cardiomyopathy can result in myocardial calcification. As dystrophic calcification can significantly affect cardiac function, clinicians should rule out cardiac calcification in patients who have had severe septic shock.

  1. [Bladder tumor lethality. Results in the autonomous community of Rioja between 1975-1991].

    Science.gov (United States)

    Fernández Fernández, A; Gil Fabra, J; Fernández Ruíz, M; Angulo Castellanos, M G; Blanco Martín, E; Otero Mauricio, G

    1998-01-01

    Between 1975-1991, a total of 557 cases of bladder carcinoma were identified in the Autonomous Community of La Rioja (CAR) which were followed up to December 1994. The overall lethality was 21.9%. 492 cases with 22.35% lethality were identified in males. In females, however, there was 65 cases with 18.46% lethality. The comparison of males and females lethality resulted in p = 0.525. Lethality between cases diagnosed within each 5-year period analyzed is: 1975-1981: 177 cases, lethality 23.72%. 1982-1986: 168 cases, lethality 30.95%. 1987-1991: 212 cases, lethality 13.20%. Between the first and the second 5-year periods, p = 0.132; between the first and third 5-year periods p = 0.007 and between the second and third 5-year periods p CAR for a 22.35% lethality. Lethality is higher in males that in females but the difference is not statistically significant. In the last 5-year period assessed, 1987-1991, a reduction of lethality from bladder neoplasms has been documented.

  2. Pressurized thermal shock (PTS)

    International Nuclear Information System (INIS)

    Rosso, Ricardo D.; Ventura, Mirta A.

    2006-01-01

    In the present work, a description of Thermal Shock in Pressurized conditions (PTS), and its influence in the treatment of the integrity of the pressure vessel (RPV) of a Pressurized Water Reactor (PWR) and/or of a Heavy water Pressurized water Reactor (PHWR) is made. Generally, the analysis of PTS involves a process of three stages: a-) Modeling with a System Code of relevant thermohydraulics transients in reference with the thermal shock; b-) The local distribution of temperatures in the downcomer and the heat transference coefficients from the RPV wall to the fluid, are determined; c-) The fracture mechanical analysis. These three stages are included in this work: Results with the thermohydraulics code Relap5/mod.3, are obtained, for a LOCA scenario in the hot leg of the cooling System of the Primary System of the CAN-I reactor. The method used in obtaining results is described. A study on the basis of lumped parameters of the local evolutions of the temperature of the flow is made, in the downcomer of the reactor pressure vessel. The purpose of this study is to determine how the intensification of the stress coefficient, varies in function of the emergency injected water during the thermohydraulic transients that take place under the imposed conditions in the postulated scene. Specially, it is considered a 50 cm 2 break, located in the neighborhoods of the pressurized with the corresponding hot leg connection. This size is considered like the most critical. The method used to obtain the results is described. The fracture mechanical analysis is made. From the obtained results we confirmed that we have a simple tool of easy application in order to analyze phenomena of the type PTS in the postulated scenes by break in the cold and hot legs of the primary system. This methodology of calculus is completely independent of the used ones by the Nucleoelectrica Argentina S.A. (NASA) in the analysis of the PTS phenomena in the CAN-I. The results obtained with the adopted

  3. Modulation of Acetylation: Creating a Pro-survival and Anti-Inflammatory Phenotype in Lethal Hemorrhagic and Septic Shock

    Science.gov (United States)

    2011-01-01

    regulating kinase 1,” Molecular and Cellular Biology, vol. 22, no. 22, pp. 7721–7730, 2002. [85] A. L. Joly , G. Wettstein, G. Mignot, F. Ghiringhelli, and C... Martin , and G. D. Wu, “Inhibition of IL-8 gene expression in Caco-2 cells by compounds which induce histone hyperacetylation,” Cytokine, vol. 9, no. 1, pp

  4. Radiation- and pair-loaded shocks

    Science.gov (United States)

    Lyutikov, Maxim

    2018-06-01

    We consider the structure of mildly relativistic shocks in dense media, taking into account the radiation and pair loading, and diffusive radiation energy transfer within the flow. For increasing shock velocity (increasing post-shock temperature), the first important effect is the efficient energy redistribution by radiation within the shock that leads to the appearance of an isothermal jump, whereby the flow reaches the final state through a discontinuous isothermal transition. The isothermal jump, on scales much smaller than the photon diffusion length, consists of a weak shock and a quick relaxation to the isothermal conditions. Highly radiation-dominated shocks do not form isothermal jump. Pair production can mildly increase the overall shock compression ratio to ≈10 (4 for matter-dominated shocks and 7 of the radiation-dominated shocks).

  5. Prediction of massive bleeding. Shock index and modified shock index.

    Science.gov (United States)

    Terceros-Almanza, L J; García-Fuentes, C; Bermejo-Aznárez, S; Prieto-Del Portillo, I J; Mudarra-Reche, C; Sáez-de la Fuente, I; Chico-Fernández, M

    2017-12-01

    To determine the predictive value of the Shock Index and Modified Shock Index in patients with massive bleeding due to severe trauma. Retrospective cohort. Severe trauma patient's initial attention at the intensive care unit of a tertiary hospital. Patients older than 14 years that were admitted to the hospital with severe trauma (Injury Severity Score >15) form January 2014 to December 2015. We studied the sensitivity (Se), specificity (Sp), positive and negative predictive value (PV+ and PV-), positive and negative likelihood ratio (LR+ and LR-), ROC curves (Receiver Operating Characteristics) and the area under the same (AUROC) for prediction of massive hemorrhage. 287 patients were included, 76.31% (219) were male, mean age was 43,36 (±17.71) years and ISS was 26 (interquartile range [IQR]: 21-34). The overall frequency of massive bleeding was 8.71% (25). For Shock Index: AUROC was 0.89 (95% confidence intervals [CI] 0.84 to 0.94), with an optimal cutoff at 1.11, Se was 91.3% (95% CI: 73.2 to 97.58) and Sp was 79.69% (95% CI: 74.34 to 84.16). For the Modified Shock Index: AUROC was 0.90 (95% CI: 0.86 to 0.95), with an optimal cutoff at 1.46, Se was 95.65% (95% CI: 79.01 to 99.23) and Sp was 75.78% (95% CI: 70.18 to 80.62). Shock Index and Modified Shock Index are good predictors of massive bleeding and could be easily incorporated to the initial workup of patients with severe trauma. Copyright © 2017 Elsevier España, S.L.U. y SEMICYUC. All rights reserved.

  6. 5-Lipoxygenase Deficiency Reduces Acetaminophen-Induced Hepatotoxicity and Lethality

    Directory of Open Access Journals (Sweden)

    Miriam S. N. Hohmann

    2013-01-01

    Full Text Available 5-Lipoxygenase (5-LO converts arachidonic acid into leukotrienes (LTs and is involved in inflammation. At present, the participation of 5-LO in acetaminophen (APAP-induced hepatotoxicity and liver damage has not been addressed. 5-LO deficient (5-LO-/- mice and background wild type mice were challenged with APAP (0.3–6 g/kg or saline. The lethality, liver damage, neutrophil and macrophage recruitment, LTB4, cytokine production, and oxidative stress were assessed. APAP induced a dose-dependent mortality, and the dose of 3 g/kg was selected for next experiments. APAP induced LTB4 production in the liver, the primary target organ in APAP toxicity. Histopathological analysis revealed that 5-LO-/- mice presented reduced APAP-induced liver necrosis and inflammation compared with WT mice. APAP-induced lethality, increase of plasma levels of aspartate aminotransferase and alanine aminotransferase, liver cytokine (IL-1β, TNF-α, IFN-γ, and IL-10, superoxide anion, and thiobarbituric acid reactive substances production, myeloperoxidase and N-acetyl-β-D-glucosaminidase activity, Nrf2 and gp91phox mRNA expression, and decrease of reduced glutathione and antioxidant capacity measured by 2,2′-azinobis(3-ethylbenzothiazoline 6-sulfonate assay were prevented in 5-LO-/- mice compared to WT mice. Therefore, 5-LO deficiency resulted in reduced mortality due to reduced liver inflammatory and oxidative damage, suggesting 5-LO is a promising target to reduce APAP-induced lethality and liver inflammatory/oxidative damage.

  7. Left ventricular function during lethal and sublethal endotoxemia in swine

    International Nuclear Information System (INIS)

    Goldfarb, R.D.; Nightingale, L.M.; Kish, P.; Weber, P.B.; Loegering, D.J.

    1986-01-01

    Previous studies suggested that after a median lethal dose (LD 50 ) of endotoxin, cardiac contractility was depressed in nonsurviving dogs. The canine cardiovascular system is unlike humans in that dogs have a hepatic vein sphincter that is susceptible to adrenergic stimulation capable of raising hepatic and splanchnic venous pressures. The authors retested the hypothesis that lethality after endotoxin administration is associated with cardiac contractile depression in pigs, because of the hepatic circulation in this species is similar to that of humans. They compared cardiac mechanical function of pigs administered a high dose (250 μg/kg) or a low dose (100 μg/kg) endotoxin by use of the slope of the end-systolic pressure-diameter relationship (ESPDR) as well as other measurements of cardiac performance. In all the pigs administered a high dose, ESPDR demonstrated a marked, time-dependent depression whereas we observed no significant ESPDR changes after low endotoxin doses. The other cardiodynamic variables were uninterpretable, due to the significant changes in heart rate, end-diastolic diameter (preload), and aortic diastolic pressure (afterload). Plasma myocardia depressant factor activity accumulated in all endotoxin-administered animals, tending to be greater in the high-dose group. In this group, both subendocardial blood flow and global function were depressed, whereas pigs administered the low dose endotoxin demonstrated slight, but nonsignificant, increases in flow and function. These observations indicate that myocardial contractile depression is associated with a lethal outcome to high doses of endotoxin. Myocardial perfusion was measured using radiolabeled microspheres infused into the left atria

  8. Rifaximin diminishes neutropenia following potentially lethal whole-body radiation.

    Science.gov (United States)

    Jahraus, Christopher D; Schemera, Bettina; Rynders, Patricia; Ramos, Melissa; Powell, Charles; Faircloth, John; Brawner, William R

    2010-07-01

    Terrorist attacks involving radiological or nuclear weapons are a substantial geopolitical concern, given that large populations could be exposed to potentially lethal doses of radiation. Because of this, evaluating potential countermeasures against radiation-induced mortality is critical. Gut microflora are the most common source of systemic infection following exposure to lethal doses of whole-body radiation, suggesting that prophylactic antibiotic therapy may reduce mortality after radiation exposure. The chemical stability, easy administration and favorable tolerability profile of the non-systemic antibiotic, rifaximin, make it an ideal potential candidate for use as a countermeasure. This study evaluated the use of rifaximin as a countermeasure against low-to-intermediate-dose whole-body radiation in rodents. Female Wistar rats (8 weeks old) were irradiated with 550 cGy to the whole body and were evaluated for 30 d. Animals received methylcellulose, neomycin (179 mg/kg/d) or variably dosed rifaximin (150-2000 mg/kg/d) one hour after irradiation and daily throughout the study period. Clinical assessments (e.g. body weight) were made daily. On postirradiation day 30, blood samples were collected and a complete blood cell count was performed. Animals receiving high doses of rifaximin (i.e. 1000 or 2000 mg/kg/d) had a greater increase in weight from the day of irradiation to postirradiation day 30 compared with animals that received placebo or neomycin. For animals with an increase in average body weight from irradiation day within 80-110% of the group average, methylcellulose rendered an absolute neutrophil count (ANC) of 211, neomycin rendered an ANC of 334, rifaximin 300 mg/kg/d rendered an ANC of 582 and rifaximin 1000 mg/kg/d rendered an ANC of 854 (P = 0.05 for group comparison). Exposure to rifaximin after near-lethal whole-body radiation resulted in diminished levels of neutropenia.

  9. Shock diffraction in alumina powder

    International Nuclear Information System (INIS)

    Venz, G.; Killen, P.D.; Page, N.W.

    1996-01-01

    In order to produce complex shaped components by dynamic compaction of ceramic powders detailed knowledge of their response under shock loading conditions is required. This work attempts to provide data on release effects and shock attenuation in 1 μm and 5 μm α-alumina powders which were compacted to between 85 % and 95 % of the solid phase density by the impact of high velocity steel projectiles. As in previous work, the powder was loaded into large cylindrical dies with horizontal marker layers of a contrasting coloured powder to provide a record of powder displacement in the recovered specimens. After recovery and infiltration with a thermosetting resin the specimens were sectioned and polished to reveal the structure formed by the passage of the projectile and shock wave. Results indicate that the shock pressures generated were of the order of 0.5 to 1.4 GPa and higher, with shock velocities and sound speeds in the ranges 650 to 800 m/s and 350 to 400 m/s respectively

  10. Transient shocks beyond the heliopause

    International Nuclear Information System (INIS)

    Fermo, R L; Pogorelov, N V; Burlaga, L F

    2015-01-01

    The heliopause is a rich, dynamic surface affected by the time-dependent solar wind. Stream interactions due to coronal mass ejections (CMEs), corotating interaction regions (CIRs), and other transient phenomena are known to merge producing global merged interaction regions (GMIRs). Numerical simulations of the solar wind interaction with the local interstellar medium (LISM) show that GMIRs, as well other time-dependent structures in the solar wind, may produce compression/rarefaction waves and shocks in the LISM behind the heliopause. These shocks may initiate wave activity observed by the Voyager spacecraft. The magnetometer onboard Voyager 1 indeed observed a few structures that may be interpreted as shocks. We present numerical simulations of such shocks in the year of 2000, when both Voyager spacecraft were in the supersonic solar wind region, and in 2012, when Voyager 1 observed traveling shocks. In the former case, Voyager observations themselves provide time- dependent boundary conditions in the solar wind. In the latter case, we use OMNI data at 1 AU to analyze the plasma and magnetic field behavior after Voyager 1 crossed the heliospheric boundary. Numerical results are compared with spacecraft observations. (paper)

  11. Ultraviolet-B lethal damage on Pseudomonas aeruginosa

    International Nuclear Information System (INIS)

    Degiorgi, C.F.; Fernandez, R.O.; Pizarro, R.A.

    1996-01-01

    Pseudomonas aeruginosa has shown an increased sensitivity compared with that of Escherichia coli and Enterobacter cloacae, when they were exposed to 0.4 kJ/m2 of ultraviolet-B radiation. The rapid decay in cell viability observed in Pseudomonas aeruginosa after the irradiation was influenced by factors such as culture media and the presence of pyocyanine during the irradiation. The radioinduced lethal damage could be prevented by photoreactivating treatment, indicating that pyrimidine dimer formation was the mechanism causing bacterial death. The results indicate that several environmental conditions may act as protective agents against ultraviolet-B-induced damage

  12. Metformin is synthetically lethal with glucose withdrawal in cancer cells.

    Science.gov (United States)

    Menendez, Javier A; Oliveras-Ferraros, Cristina; Cufí, Sílvia; Corominas-Faja, Bruna; Joven, Jorge; Martin-Castillo, Begoña; Vazquez-Martin, Alejandro

    2012-08-01

    Glucose deprivation is a distinctive feature of the tumor microecosystem caused by the imbalance between poor supply and an extraordinarily high consumption rate. The metabolic reprogramming from mitochondrial respiration to aerobic glycolysis in cancer cells (the "Warburg effect") is linked to oncogenic transformation in a manner that frequently implies the inactivation of metabolic checkpoints such as the energy rheostat AMP-activated protein kinase (AMPK). Because the concept of synthetic lethality in oncology can be applied not only to genetic and epigenetic intrinsic differences between normal and cancer cells but also to extrinsic ones such as altered microenvironment, we recently hypothesized that stress-energy mimickers such as the AMPK agonist metformin should produce metabolic synthetic lethality in a glucose-starved cell culture milieu imitating the adverse tumor growth conditions in vivo. Under standard high-glucose conditions, metformin supplementation mostly caused cell cycle arrest without signs of apoptotic cell death. Under glucose withdrawal stress, metformin supplementation circumvented the ability of oncogenes (e.g., HER2) to protect breast cancer cells from glucose-deprivation apoptosis. Significantly, representative cell models of breast cancer heterogeneity underwent massive apoptosis (by >90% in some cases) when glucose-starved cell cultures were supplemented with metformin. Our current findings may uncover crucial issues regarding the cell-autonomous metformin's anti-cancer actions: (1) The offently claimed clinically irrelevant, non-physiological concentrations needed to observe the metformin's anti-cancer effects in vitro merely underlie the artifactual interference of erroneous glucose-rich experimental conditions that poorly reflect glucose-starved in vivo conditions; (2) the preferential killing of cancer stem cells (CSC) by metformin may simply expose the best-case scenario for its synthetically lethal activity because an increased

  13. Genotoxicity test of irradiated spice mixture by dominant lethal test

    Energy Technology Data Exchange (ETDEWEB)

    Barna, J

    1986-03-01

    Dominant lethal test (DLT) was performed in Sprague Dawley male rats prefed with 25% irradiated spice mixture which was composed of 55% non-pungent ground paprika, 14% black pepper, 9% allspice, 9% coriander, 7% marjoram, 4% cumin, 2% nutmeg. Microbial count of the spice mixture was reduced with 15 kGy from a sup(60)Co source. Control groups received spice-free or untreated spice diet or were administered to cyclophosphamide i.p., respectively. DTL parameters altered significantly in the latter group but neither untreated nor irradiated spice mixture proved to be germ cell mutagens. 24 refs.; 8 figs.

  14. Lethal subarachnoid bleeding under immunosuppressive therapy due to mycotic arteritis

    International Nuclear Information System (INIS)

    Weigel, S.; Kloska, S.; Freund, M.; Kehl, H.G.

    2003-01-01

    A subarachnoid haemorrhage (SAH) occurred 67 days after cardiac transplantation in 10-year-old girl with consecutive immunocompromising therapy. Neither digital subtraction angiography (DSA) nor computed tomographic angiography showed signs of intracranial vascular malformations. One month before the lethal SAH occurred, she had developed arterial hypertension and attacks of severe headache with cerebrospinal fluid (CSF) pleocytosis while CT scans showed an infarct of the left thalamus. Pathologic findings established the rare diagnosis of SAH due to aspergillosis-related mycotic arteritis. Imaging characteristics are presented. (orig.)

  15. Energetic ion acceleration at collisionless shocks

    Science.gov (United States)

    Decker, R. B.; Vlahos, L.

    1985-01-01

    An example is presented from a test particle simulation designed to study ion acceleration at oblique turbulent shocks. For conditions appropriate at interplanetary shocks near 1 AU, it is found that a shock with theta sub B n = 60 deg is capable of producing an energy spectrum extending from 10 keV to approx. 1 MeV in approx 1 hour. In this case total energy gains result primarily from several separate episodes of shock drift acceleration, each of which occurs when particles are scattered back to the shock by magnetic fluctuations in the shock vicinity.

  16. Energetic ion acceleration at collisionless shocks

    International Nuclear Information System (INIS)

    Decker, R.B.; Vlahos, L.

    1985-01-01

    An example is presented from a test particle simulation designed to study ion acceleration at oblique turbulent shocks. For conditions appropriate at interplanetary shocks near 1 AU, it is found that a shock with theta sub B n = 60 deg is capable of producing an energy spectrum extending from 10 keV to approx 1 MeV in approx 1 hour. In this case total energy gains result primarily from several separate episodes of shock drift acceleration, each of which occurs when particles are scattered back to the shock by magnetic fluctuations in the shock vicinity

  17. Why the Nature of Oil Shocks Matters

    International Nuclear Information System (INIS)

    Archanskaia, Elizaveta; Hubert, Paul; Creel, Jerome

    2009-03-01

    This article studies the impact of oil shocks on the macro-economy in two ways insofar unexploited in the literature. The analysis is conducted at the global level, and it explicitly accounts for the potentially changing nature of oil shocks. Based on an original world GDP series and a grouping of oil shocks according to their nature, we find that oil supply shocks negatively impact world growth, contrary to oil demand shocks, pro-cyclical in their nature. This result is robust at the national level for the US. Furthermore, endogenous monetary policy is shown to have no counter-cyclical effects in the context of an oil demand shock. (authors)

  18. MHD intermediate shock discontinuities: Pt. 1

    International Nuclear Information System (INIS)

    Kennel, C.F.; Blandford, R.D.; Coppi, P.

    1989-01-01

    Recent numerical investigations have focused attention once more on the role of intermediate shocks in MHD. Four types of intermediate shock are identified using a graphical representation of the MHD Rankine-Hugoniot conditions. This same representation can be used to exhibit the close relationship of intermediate shocks to switch-on shocks and rotational discontinuities. The conditions under which intermediate discontinuities can be found are elucidated. The variations in velocity, pressure, entropy and magnetic-field jumps with upstream parameters in intermediate shocks are exhibited graphically. The evolutionary arguments traditionally advanced against intermediate shocks may fail because the equations of classical MHD are not strictly hyperbolic. (author)

  19. Shock waves in weakly compressed granular media.

    Science.gov (United States)

    van den Wildenberg, Siet; van Loo, Rogier; van Hecke, Martin

    2013-11-22

    We experimentally probe nonlinear wave propagation in weakly compressed granular media and observe a crossover from quasilinear sound waves at low impact to shock waves at high impact. We show that this crossover impact grows with the confining pressure P0, whereas the shock wave speed is independent of P0-two hallmarks of granular shocks predicted recently. The shocks exhibit surprising power law attenuation, which we model with a logarithmic law implying that shock dissipation is weak and qualitatively different from other granular dissipation mechanisms. We show that elastic and potential energy balance in the leading part of the shocks.

  20. Shock, diaschisis and von Monakow

    Directory of Open Access Journals (Sweden)

    Eliasz Engelhardt

    2013-07-01

    Full Text Available The concept of shock apparently emerged in the middle of the 18th century (Whyett as an occurrence observed experimentally after spinal cord transection, and identified as "shock" phenomenon one century later (Hall. The concept was extended (Brown-Séquard and it was suggested that brain lesions caused functional rupture in regions distant from the injured one ("action à distance". The term "diaschisis" (von Monakow, proposed as a new modality of shock, had its concept broadened, underpinned by observations of patients, aiming at distinguishing between symptoms of focal brain lesions and transitory effects they produced, attributable to depression of distant parts of the brain connected to the injured area. Presently, diaschisis is related mainly to cerebrovascular lesions and classified according to the connection fibers involved, as proposed by von Monakow. Depression of metabolism and blood flow in regions anatomically separated, but related by connections with the lesion, allows observing diaschisis with neuroimaging.

  1. Shock compression of geological materials

    International Nuclear Information System (INIS)

    Kirk, S; Braithwaite, C; Williamson, D; Jardine, A

    2014-01-01

    Understanding the shock compression of geological materials is important for many applications, and is particularly important to the mining industry. During blast mining the response to shock loading determines the wave propagation speed and resulting fragmentation of the rock. The present work has studied the Hugoniot of two geological materials; Lake Quarry Granite and Gosford Sandstone. For samples of these materials, the composition was characterised in detail. The Hugoniot of Lake Quarry Granite was predicted from this information as the material is fully dense and was found to be in good agreement with the measured Hugoniot. Gosford Sandstone is porous and undergoes compaction during shock loading. Such behaviour is similar to other granular material and we show how it can be described using a P-a compaction model.

  2. Shock compression of simulated adobe

    Science.gov (United States)

    Braithwaite, C. H.; Church, P. D.; Gould, P. J.; Stewart, B.; Jardine, A. P.

    2017-01-01

    A series of plate impact experiments were conducted to investigate the shock response of a simulant for adobe, a traditional form of building material widely used around the world. Air dried bricks were sourced from the London brick company, dry machined and impacted at a range of velocities in a single stage gas gun. The shock Hugoniot was determined (Us =2.26up+0.37) as well as release information. The material was found to behave in a manner which was similar to that of loose sand and considerably less stiff than a weak porous sandstone. The effect of any cementing of the grains was examined by shocking powdered samples contained within a cell arrangement.

  3. Acute lethal toxicity following passive immunization for treatment of murine cryptococcosis.

    Science.gov (United States)

    Savoy, A C; Lupan, D M; Manalo, P B; Roberts, J S; Schlageter, A M; Weinhold, L C; Kozel, T R

    1997-01-01

    Passive immunization with monoclonal antibodies (MAbs) specific for the major capsular polysaccharide of Cryptococcus neoformans alters the course of murine cryptococcosis. During studies of passive immunization for treatment of murine cryptococcosis, we noted the occurrence of an acute, lethal toxicity. Toxicity was characterized by scratching, lethargy, respiratory distress, collapse, and death within 20 to 60 min after injection of antibody. The toxic effect was observed only in mice with a cryptococcal infection and was reduced or absent in the early and late stages of disease. The clinical course and histopathology were consistent with those for shock. There was considerable variation between mouse strains in susceptibility to toxicity. Swiss Webster mice from the Charles River colony were most susceptible, followed by C3H/He, BALB/c, and C57BL/6 mice. DBA/2 mice and Swiss Webster mice from the Simonsen colony were resistant. Acute toxicity was mimicked by injection of preformed complexes of MAb and purified polysaccharide. The toxic effect was also produced by injection of MAbs into mice that were preloaded with polysaccharide. The toxic effect was not blocked by treatment of mice with chloropheniramine or anti-tumor necrosis factor alpha antibodies or by depletion of complement components via pretreatment with cobra venom factor. Toxicity was reduced by treatment of mice with high doses of epinephrine, dexamethasone, or chlorpromazine. Finally, the toxic effect was completely blocked by treatment of mice with the platelet-activating factor antagonist WEB 2170 BS or by pretreatment of mice with the liposome-encapsulated drug dichloromethylene diphosphonate, a procedure which depletes macrophages from the spleen and liver. PMID:9125564

  4. Shock Initiation of Damaged Explosives

    Energy Technology Data Exchange (ETDEWEB)

    Chidester, S K; Vandersall, K S; Tarver, C M

    2009-10-22

    Explosive and propellant charges are subjected to various mechanical and thermal insults that can increase their sensitivity over the course of their lifetimes. To quantify this effect, shock initiation experiments were performed on mechanically and thermally damaged LX-04 (85% HMX, 15% Viton by weight) and PBX 9502 (95% TATB, 5% Kel-F by weight) to obtain in-situ manganin pressure gauge data and run distances to detonation at various shock pressures. We report the behavior of the HMX-based explosive LX-04 that was damaged mechanically by applying a compressive load of 600 psi for 20,000 cycles, thus creating many small narrow cracks, or by cutting wedge shaped parts that were then loosely reassembled, thus creating a few large cracks. The thermally damaged LX-04 charges were heated to 190 C for long enough for the beta to delta solid - solid phase transition to occur, and then cooled to ambient temperature. Mechanically damaged LX-04 exhibited only slightly increased shock sensitivity, while thermally damaged LX-04 was much more shock sensitive. Similarly, the insensitive explosive PBX 9502 was mechanically damaged using the same two techniques. Since PBX 9502 does not undergo a solid - solid phase transition but does undergo irreversible or 'rachet' growth when thermally cycled, thermal damage to PBX 9502 was induced by this procedure. As for LX-04, the thermally damaged PBX 9502 demonstrated a greater shock sensitivity than mechanically damaged PBX 9502. The Ignition and Growth reactive flow model calculated the increased sensitivities by igniting more damaged LX-04 and PBX 9502 near the shock front based on the measured densities (porosities) of the damaged charges.

  5. Shock compaction of molybdenum powder

    Science.gov (United States)

    Ahrens, T. J.; Kostka, D.; Vreeland, T., Jr.; Schwarz, R. B.; Kasiraj, P.

    1983-01-01

    Shock recovery experiments which were carried out in the 9 to 12 GPa range on 1.4 distension Mo and appear adequate to compact to full density ( 45 (SIGMA)m) powders were examined. The stress levels, however, are below those calculated to be from 100 to approx. 22 GPa which a frictional heating model predicts are required to consolidate approx. 10 to 50 (SIGMA)m particles. The model predicts that powders that have a distension of m=1.6 shock pressures of 14 to 72 GPa are required to consolidate Mo powders in the 50 to 10 (SIGMA)m range.

  6. Cation disorder in shocked orthopyroxene.

    Science.gov (United States)

    Dundon, R. W.; Hafner, S. S.

    1971-01-01

    The study of cation distributions over nonequivalent lattice sites in minerals may reveal information on the history of temperature and pressure in rocks. Chemically homogeneous orthopyroxene specimens were shocked under well-controlled conditions in the laboratory in order to provide a basis for the interpretation of more complex natural materials. As a result of the investigation it is concluded that the distribution of magnesium and iron over the M1 and M2 positions in Bamle enstatite shocked at 1 megabar is highly disordered. It corresponds to an equilibrium distribution of at least 1000 C.

  7. Sepsis and Septic Shock Strategies.

    Science.gov (United States)

    Armstrong, Bracken A; Betzold, Richard D; May, Addison K

    2017-12-01

    Three therapeutic principles most substantially improve organ dysfunction and survival in sepsis: early, appropriate antimicrobial therapy; restoration of adequate cellular perfusion; timely source control. The new definitions of sepsis and septic shock reflect the inadequate sensitivity, specify, and lack of prognostication of systemic inflammatory response syndrome criteria. Sequential (sepsis-related) organ failure assessment more effectively prognosticates in sepsis and critical illness. Inadequate cellular perfusion accelerates injury and reestablishing perfusion limits injury. Multiple organ systems are affected by sepsis and septic shock and an evidence-based multipronged approach to systems-based therapy in critical illness results in improve outcomes. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Experimental evaluation of the relationship between lethal or non-lethal virulence and transmission success in malaria parasite infections

    Directory of Open Access Journals (Sweden)

    Nithiuthai S

    2004-09-01

    Full Text Available Abstract Background Evolutionary theory suggests that the selection pressure on parasites to maximize their transmission determines their optimal host exploitation strategies and thus their virulence. Establishing the adaptive basis to parasite life history traits has important consequences for predicting parasite responses to public health interventions. In this study we examine the extent to which malaria parasites conform to the predicted adaptive trade-off between transmission and virulence, as defined by mortality. The majority of natural infections, however, result in sub-lethal virulent effects (e.g. anaemia and are often composed of many strains. Both sub-lethal effects and pathogen population structure have been theoretically shown to have important consequences for virulence evolution. Thus, we additionally examine the relationship between anaemia and transmission in single and mixed clone infections. Results Whereas there was a trade-off between transmission success and virulence as defined by host mortality, contradictory clone-specific patterns occurred when defining virulence by anaemia. A negative relationship between anaemia and transmission success was found for one of the parasite clones, whereas there was no relationship for the other. Notably the two parasite clones also differed in a transmission phenotype (gametocyte sex ratio that has previously been shown to respond adaptively to a changing blood environment. In addition, as predicted by evolutionary theory, mixed infections resulted in increased anaemia. The increased anaemia was, however, not correlated with any discernable parasite trait (e.g. parasite density or with increased transmission. Conclusions We found some evidence supporting the hypothesis that there is an adaptive basis correlating virulence (as defined by host mortality and transmission success in malaria parasites. This confirms the validity of applying evolutionary virulence theory to biomedical

  9. Lethal Nipah virus infection induces rapid overexpression of CXCL10.

    Directory of Open Access Journals (Sweden)

    Cyrille Mathieu

    Full Text Available Nipah virus (NiV is a recently emerged zoonotic Paramyxovirus that causes regular outbreaks in East Asia with mortality rate exceeding 75%. Major cellular targets of NiV infection are endothelial cells and neurons. To better understand virus-host interaction, we analyzed the transcriptome profile of NiV infection in primary human umbilical vein endothelial cells. We further assessed some of the obtained results by in vitro and in vivo methods in a hamster model and in brain samples from NiV-infected patients. We found that NiV infection strongly induces genes involved in interferon response in endothelial cells. Among the top ten upregulated genes, we identified the chemokine CXCL10 (interferon-induced protein 10, IP-10, an important chemoattractant involved in the generation of inflammatory immune response and neurotoxicity. In NiV-infected hamsters, which develop pathology similar to what is seen in humans, expression of CXCL10 mRNA was induced in different organs with kinetics that followed NiV replication. Finally, we showed intense staining for CXCL10 in the brain of patients who succumbed to lethal NiV infection during the outbreak in Malaysia, confirming induction of this chemokine in fatal human infections. This study sheds new light on NiV pathogenesis, indicating the role of CXCL10 during the course of infection and suggests that this chemokine may serve as a potential new marker for lethal NiV encephalitis.

  10. Parental response to severe or lethal prenatal diagnosis

    DEFF Research Database (Denmark)

    Lou, Stina; Jensen, Lotte Groth; Petersen, Olav Bjørn

    2017-01-01

    Objective A severe or lethal prenatal diagnosis places great demands on prospective parents, who face choices of far-reaching consequences, such as continuing or terminating the pregnancy. How best to support these parents is a clinical challenge. This systematic review aimed to identify and synt......Objective A severe or lethal prenatal diagnosis places great demands on prospective parents, who face choices of far-reaching consequences, such as continuing or terminating the pregnancy. How best to support these parents is a clinical challenge. This systematic review aimed to identify...... and synthesize the qualitative evidence regarding prospective parents’ responses to such prenatal diagnoses. Methods Following PRISMA guidelines, four databases were systematically searched and 28 studies met the inclusion criteria. Thematic analysis guided data extraction and synthesis of findings. The CERQual....... Prospective parents who continued the pregnancy wished to be acknowledged as parents, and engaged in planning to obtain a sense of meaning and control. Selective disclosure and concerns about negative responses were issues both for the parents who terminated and those who continued a pregnancy. Conclusion...

  11. Cell lethality after selective irradiation of the DNA replication fork

    International Nuclear Information System (INIS)

    Hofer, K.G.; Warters, R.L.

    1985-01-01

    It has been suggested that nascent DNA located at the DNA replication fork may exhibit enhanced sensitivity to radiation damage. To evaluate this hypothesis, Chinese hamster ovary cells (CHO) were labeled with 125 I-iododeoxyuridine ( 125 IUdR) either in the presence or absence of aphidicolin. Aphidicolin (5 μg/ml) reduced cellular 125 IUdR incorporation to 3-5% of the control value. The residual 125 I incorporation appeared to be restricted to low molecular weight (sub-replicon sized) fragments of DNA which were more sensitive to micrococcal nuclease attack and less sensitive to high salt DNase I digestion than randomly labeled DNA. These findings suggest that DNA replicated in the presence of aphidicolin remains localized at the replication fork adjacent to the nuclear matrix. Based on these observations an attempt was made to compare the lethal consequences of 125 I decays at the replication fork to that of 125 I decays randomly distributed over the entire genome. Regardless of the distribution of decay events, all treatment groups exhibited identical dose-response curves (D 0 : 101 125 I decays/cell). Since differential irradiation of the replication complex did not result in enhanced cell lethality, it can be concluded that neither the nascent DNA nor the protein components (replicative enzymes, nuclear protein matrix) associated with the DNA replication site constitute key radiosensitive targets within the cellular genome. (orig.)

  12. Lethal mutation of internal irradiation brown planthopper (Nilaparvita lugens Stal)

    International Nuclear Information System (INIS)

    Wahid, R.A.

    1988-01-01

    The moulting IVth of BPH nympha were irradiated internally with radiophosphorous 32-P 1 uCi/ml, 10 uCi/ml, 50 uCi/ml, 100 uCi/ml, and 500 uCi/ml concentrations respectivelly. An observation was carried out to determines heredity of hopper sterilities from the mating groups of R male x N female, R male x R female, and N male x R female. The 32-P concentration below of 50 uCi/ml seemed to be the substerile dose, however, the dominant lethal mutation has been visually shown by R male x R female F1 mating group. The hereditary lines of F1, F2, F3, and F4 of the hopper sterilities wich were indicated by the nympha hatch ability have some significant correlations (r1= -0.77, r2= -0.92, r3= -0.93 and r4= -0.85). Thus, the resesif lethal mutations visually showed by F3 and F4 from all of the 100 uCi/ml and 50 uCi/ml treated groups. (author). 10 refs, 2 figs, 2 tabs

  13. Shock/shock interactions between bodies and wings

    Directory of Open Access Journals (Sweden)

    Gaoxiang XIANG

    2018-02-01

    Full Text Available This paper examines the Shock/Shock Interactions (SSI between the body and wing of aircraft in supersonic flows. The body is simplified to a flat wedge and the wing is assumed to be a sharp wing. The theoretical spatial dimension reduction method, which transforms the 3D problem into a 2D one, is used to analyze the SSI between the body and wing. The temperature and pressure behind the Mach stem induced by the wing and body are obtained, and the wave configurations in the corner are determined. Numerical validations are conducted by solving the inviscid Euler equations in 3D with a Non-oscillatory and Non-free-parameters Dissipative (NND finite difference scheme. Good agreements between the theoretical and numerical results are obtained. Additionally, the effects of the wedge angle and sweep angle on wave configurations and flow field are considered numerically and theoretically. The influences of wedge angle are significant, whereas the effects of sweep angle on wave configurations are negligible. This paper provides useful information for the design and thermal protection of aircraft in supersonic and hypersonic flows. Keywords: Body and wing, Flow field, Hypersonic flow, Shock/shock interaction, Wave configurations

  14. IDENTIFICATION AND DESCRIPTION OF A NOVEL MURINE MODEL FOR POLYTRAUMA AND SHOCK

    Science.gov (United States)

    Gentile, Lori F; Nacionales, Dina C; Cuenca, Alex G; Armbruster, Michael; Ungaro, Ricardo F; Abouhamze, Amer S; Lopez, Cecelia; Baker, Henry V; Moore, Frederick A; Ang, Darwin N; Efron, Philip A

    2013-01-01

    Objective To develop a novel polytrauma model that better recapitulates the immunological response of the severely injured patient by combining long-bone fracture, muscle tissue damage and cecectomy with hemorrhagic shock, resulting in an equivalent Injury Severity Score of greater than 15. We compared this new polytrauma/shock model to historically-used murine trauma-hemorrhage models. Design Pre-clinical controlled in vivo laboratory study. Setting Laboratory of Inflammation Biology and Surgical Science. Subjects 6–10 wk old C57BL/6 (B6) mice Interventions Mice underwent 90 minutes of shock (MAP 30 mmHg) and resuscitation via femoral artery cannulation followed by either laparotomy (TH), laparotomy with femur fracture (H+FFx), or laparotomy with cecetomy and femur fracture with muscle tissue damage (PT). Mice were euthanized at two hours, one day and three days post injury. Measurements and Main Results The spleen, bone marrow, blood, and serum were collected from mice for analysis at the above time points. None of the models were lethal. Mice undergoing PT exhibited a more robust inflammatory response with significant elevations in cytokine/chemokine concentrations when compared to traditional models. PT was the only model to induce neutrophilia (Ly6G+CD11b+ cells) on days 1 and 3 (ppolytrauma model better replicates the human leukocyte, cytokine, and overall inflammatory response following injury and hemorrhagic shock. PMID:23399937

  15. Potentiation of radiation lethality by Topotecan, a Topoisomerase I inhibitor

    International Nuclear Information System (INIS)

    Lamond, J.P.; Kinsella, T.J.; Boothman, D.A.

    1995-01-01

    Purpose/Objective: Topotecan is a water soluble Topoisomerase I (Topo I) inhibitor that has demonstrated antineoplastic activity in phase I/II trials of solid tumors (such as non-small cell lung, small cell lung, ovarian, esophageal and head and neck primaries) and leukemias. We sought to determine (1) if Topotecan potentiated the lethal effects of ionizing radiation, and (2) the characteristics of the synergistic effect. Materials and Methods: Human radioresistant melanoma (U1-Mel) and glioma (D54) cells were grown in Dulbecco's modified Eagle's medium (DME) with 10% fetal calf serum (FCS) until confluence-arrest. Cells were x-irradiated (0-700 cGy) and exposed to various Topotecan concentrations (2-100μM), either before (for 4 hours), during, or after (for 4 hours) irradiation. Appropriate controls were also performed. Survival was determined via colony forming assays. Survival curves were normalized to correct for drug cytotoxicities and variations in initial viable cells plated. In another set of experiments, U1-Mel cells were exposed to 10 μM Topotecan either before, during or after 400 cGy, as described above. A modification of the SDS and KCl assay was used to quantify Topo I-DNA complexes via glass fiber filter binding. All experiments were performed at least 7 times in duplicate. Results: Potentiation of radiation lethality was seen in the U1-Mel and D54 cell lines. The synergistic effects were (1) dependent on drug concentration, with lethality enhancement and minimal drug lethality alone in the 2-10 μM range (2) dependent on timing, with synergy present only when the drug was present at the time of, or shortly after irradiation, and (3) irreversible, with inhibition of potential lethal damage repair (PLDR). The dose enhancement ratios (DER) for 4 μM Topotecan in the U1-Mel cells was 1.7 - 2.4, depending on the survival endpoints that were used. The DER for 2 μM Topotecan in D54 cells was 3.0 - 4.0. The U1-Mel cells that were exposed to Topotecan

  16. Analytical solutions of hypersonic type IV shock - shock interactions

    Science.gov (United States)

    Frame, Michael John

    An analytical model has been developed to predict the effects of a type IV shock interaction at high Mach numbers. This interaction occurs when an impinging oblique shock wave intersects the most normal portion of a detached bow shock. The flowfield which develops is complicated and contains an embedded jet of supersonic flow, which may be unsteady. The jet impinges on the blunt body surface causing very high pressure and heating loads. Understanding this type of interaction is vital to the designers of cowl lips and leading edges on air- breathing hypersonic vehicles. This analytical model represents the first known attempt at predicting the geometry of the interaction explicitly, without knowing beforehand the jet dimensions, including the length of the transmitted shock where the jet originates. The model uses a hyperbolic equation for the bow shock and by matching mass continuity, flow directions and pressure throughout the flowfield, a prediction of the interaction geometry can be derived. The model has been shown to agree well with the flowfield patterns and properties of experiments and CFD, but the prediction for where the peak pressure is located, and its value, can be significantly in error due to a lack of sophistication in the model of the jet fluid stagnation region. Therefore it is recommended that this region of the flowfield be modeled in more detail and more accurate experimental and CFD measurements be used for validation. However, the analytical model has been shown to be a fast and economic prediction tool, suitable for preliminary design, or for understanding the interactions effects, including the basic physics of the interaction, such as the jet unsteadiness. The model has been used to examine a wide parametric space of possible interactions, including different Mach number, impinging shock strength and location, and cylinder radius. It has also been used to examine the interaction on power-law shaped blunt bodies, a possible candidate for

  17. "Driverless" Shocks in the Interplanetary Medium

    Science.gov (United States)

    Gopalswamy, N.; Kaiser, M. L.; Lara, A.

    1999-01-01

    Many interplanetary shocks have been detected without an obvious driver behind them. These shocks have been thought to be either blast waves from solar flares or shocks due to sudden increase in solar wind speed caused by interactions between large scale open and closed field lines of the Sun. We investigated this problem using a set of interplanetary shock detected {\\it in situ} by the Wind space craft and tracing their solar origins using low frequency radio data obtained by the Wind/WAVES experiment. For each of these "driverless shocks" we could find a unique coronal mass ejections (CME) event observed by the SOHO (Solar and Heliospheric Observatory) coronagraphs. We also found that these CMEs were ejected at large angles from the Sun-Earth line. It appears that the "driverless shocks" are actually driver shocks, but the drivers were not intercepted by the spacecraft. We conclude that the interplanetary shocks are much more extended than the driving CMEs.

  18. Shock and Vibration. Volume 1, Issue 1

    National Research Council Canada - National Science Library

    Pilkey, Walter D

    1994-01-01

    ..., and earthquake engineering. Among the specific areas to be covered are vibration testing and control, vibration condition monitoring and diagnostics, shock hardenings, modal technology, shock testing, data acquisition, fluid...

  19. Initial ISEE magnetometer results: shock observation

    International Nuclear Information System (INIS)

    Russell, C.T.

    1979-01-01

    ISEE-1 and -2 magnetic field profiles across 6 terrestrial bow shock and one interplanetary shock are examined. The inteplanetary shock illustrates the behavior of a low Mach number shock. Three examples of low or moderate β, high Mach number, quasi-perpendicular shocks are examined. These did not have upstream waves, but rather had waves growing in the field gradient. Two examples of high β shocks showed little coherence in field variation even though the two vehicles were only a few hundred kilometers apart. The authors present the joint behavior of wave, particle and field data across some of these shocks to show some of the myriad of shock features whose behavior they are now beginning to investigate. (Auth.)

  20. 29th International Symposium on Shock Waves

    CERN Document Server

    Ranjan, Devesh

    2015-01-01

    This proceedings present the results of the 29th International Symposium on Shock Waves (ISSW29) which was held in Madison, Wisconsin, U.S.A., from July 14 to July 19, 2013. It was organized by the Wisconsin Shock Tube Laboratory, which is part of the College of Engineering of the University of Wisconsin-Madison. The ISSW29 focused on the following areas: Blast Waves, Chemically Reactive Flows, Detonation and Combustion,  Facilities, Flow Visualization, Hypersonic Flow, Ignition, Impact and Compaction, Industrial Applications, Magnetohydrodynamics, Medical and Biological Applications, Nozzle Flow, Numerical Methods, Plasmas, Propulsion, Richtmyer-Meshkov Instability, Shock-Boundary Layer Interaction, Shock Propagation and Reflection, Shock Vortex Interaction, Shock Waves in Condensed Matter, Shock Waves in Multiphase Flow, as well as Shock Waves in Rarefield Flow. The two Volumes contain the papers presented at the symposium and serve as a reference for the participants of the ISSW 29 and individuals interes...

  1. Inferior vena cava obstruction and shock

    Directory of Open Access Journals (Sweden)

    Megri Mohammed

    2018-01-01

    Full Text Available Shock is one of the most challenging life-threatening conditions with high mortality and morbidity; the outcomes are highly dependent on the early detection and management of the condition. Septic shock is the most common type of shock in the Intensive Care Unit. While not as common as other subsets of shock, obstructive shock is a significant subtype due to well defined mechanical and pathological causes, including tension pneumothorax, massive pulmonary embolism, and cardiac tamponade. We are presenting a patient with obstructive shock due to inferior vena cava obstruction secondary to extensive deep venous thrombosis. Chance of survival from obstructive shock in our patient was small; however, there was complete and immediate recovery after treatment of the obstruction on recognizing the affected vessels. This case alerts the practicing intensivist and the emergency medicine physician to consider occlusion of the great vessels other than the pulmonary artery or aorta as causes of obstructive shock.

  2. Shock dynamics in layered periodic media

    KAUST Repository

    Ketcheson, David I.

    2012-01-01

    Solutions of constant-coeffcient nonlinear hyperbolic PDEs generically develop shocks, even if the initial data is smooth. Solutions of hyperbolic PDEs with variable coeffcients can behave very differently. We investigate formation and stability of shock waves in a one-dimensional periodic layered medium by a computational study of time-reversibility and entropy evolution. We find that periodic layered media tend to inhibit shock formation. For small initial conditions and large impedance variation, no shock formation is detected even after times much greater than the time of shock formation in a homogeneous medium. Furthermore, weak shocks are observed to be dynamically unstable in the sense that they do not lead to significant long-term entropy decay. We propose a characteristic condition for admissibility of shocks in heterogeneous media that generalizes the classical Lax entropy condition and accurately predicts the formation or absence of shocks in these media.

  3. Converging cylindrical shocks in ideal magnetohydrodynamics

    International Nuclear Information System (INIS)

    Pullin, D. I.; Mostert, W.; Wheatley, V.; Samtaney, R.

    2014-01-01

    We consider a cylindrically symmetrical shock converging onto an axis within the framework of ideal, compressible-gas non-dissipative magnetohydrodynamics (MHD). In cylindrical polar co-ordinates we restrict attention to either constant axial magnetic field or to the azimuthal but singular magnetic field produced by a line current on the axis. Under the constraint of zero normal magnetic field and zero tangential fluid speed at the shock, a set of restricted shock-jump conditions are obtained as functions of the shock Mach number, defined as the ratio of the local shock speed to the unique magnetohydrodynamic wave speed ahead of the shock, and also of a parameter measuring the local strength of the magnetic field. For the line current case, two approaches are explored and the results compared in detail. The first is geometrical shock-dynamics where the restricted shock-jump conditions are applied directly to the equation on the characteristic entering the shock from behind. This gives an ordinary-differential equation for the shock Mach number as a function of radius which is integrated numerically to provide profiles of the shock implosion. Also, analytic, asymptotic results are obtained for the shock trajectory at small radius. The second approach is direct numerical solution of the radially symmetric MHD equations using a shock-capturing method. For the axial magnetic field case the shock implosion is of the Guderley power-law type with exponent that is not affected by the presence of a finite magnetic field. For the axial current case, however, the presence of a tangential magnetic field ahead of the shock with strength inversely proportional to radius introduces a length scale R=√(μ 0 /p 0 ) I/(2 π) where I is the current, μ 0 is the permeability, and p 0 is the pressure ahead of the shock. For shocks initiated at r ≫ R, shock convergence is first accompanied by shock strengthening as for the strictly gas-dynamic implosion. The diverging magnetic field

  4. Converging cylindrical shocks in ideal magnetohydrodynamics

    KAUST Repository

    Pullin, D. I.

    2014-09-01

    We consider a cylindrically symmetrical shock converging onto an axis within the framework of ideal, compressible-gas non-dissipative magnetohydrodynamics (MHD). In cylindrical polar co-ordinates we restrict attention to either constant axial magnetic field or to the azimuthal but singular magnetic field produced by a line current on the axis. Under the constraint of zero normal magnetic field and zero tangential fluid speed at the shock, a set of restricted shock-jump conditions are obtained as functions of the shock Mach number, defined as the ratio of the local shock speed to the unique magnetohydrodynamic wave speed ahead of the shock, and also of a parameter measuring the local strength of the magnetic field. For the line current case, two approaches are explored and the results compared in detail. The first is geometrical shock-dynamics where the restricted shock-jump conditions are applied directly to the equation on the characteristic entering the shock from behind. This gives an ordinary-differential equation for the shock Mach number as a function of radius which is integrated numerically to provide profiles of the shock implosion. Also, analytic, asymptotic results are obtained for the shock trajectory at small radius. The second approach is direct numerical solution of the radially symmetric MHD equations using a shock-capturing method. For the axial magnetic field case the shock implosion is of the Guderley power-law type with exponent that is not affected by the presence of a finite magnetic field. For the axial current case, however, the presence of a tangential magnetic field ahead of the shock with strength inversely proportional to radius introduces a length scale R = √μ0/p0 I/(2π) where I is the current, μ0 is the permeability, and p0 is the pressure ahead of the shock. For shocks initiated at r ≫ R, shock convergence is first accompanied by shock strengthening as for the strictly gas-dynamic implosion. The diverging magnetic field then

  5. Converging cylindrical shocks in ideal magnetohydrodynamics

    KAUST Repository

    Pullin, D. I.; Mostert, W.; Wheatley, V.; Samtaney, Ravi

    2014-01-01

    We consider a cylindrically symmetrical shock converging onto an axis within the framework of ideal, compressible-gas non-dissipative magnetohydrodynamics (MHD). In cylindrical polar co-ordinates we restrict attention to either constant axial magnetic field or to the azimuthal but singular magnetic field produced by a line current on the axis. Under the constraint of zero normal magnetic field and zero tangential fluid speed at the shock, a set of restricted shock-jump conditions are obtained as functions of the shock Mach number, defined as the ratio of the local shock speed to the unique magnetohydrodynamic wave speed ahead of the shock, and also of a parameter measuring the local strength of the magnetic field. For the line current case, two approaches are explored and the results compared in detail. The first is geometrical shock-dynamics where the restricted shock-jump conditions are applied directly to the equation on the characteristic entering the shock from behind. This gives an ordinary-differential equation for the shock Mach number as a function of radius which is integrated numerically to provide profiles of the shock implosion. Also, analytic, asymptotic results are obtained for the shock trajectory at small radius. The second approach is direct numerical solution of the radially symmetric MHD equations using a shock-capturing method. For the axial magnetic field case the shock implosion is of the Guderley power-law type with exponent that is not affected by the presence of a finite magnetic field. For the axial current case, however, the presence of a tangential magnetic field ahead of the shock with strength inversely proportional to radius introduces a length scale R = √μ0/p0 I/(2π) where I is the current, μ0 is the permeability, and p0 is the pressure ahead of the shock. For shocks initiated at r ≫ R, shock convergence is first accompanied by shock strengthening as for the strictly gas-dynamic implosion. The diverging magnetic field then

  6. Converging cylindrical shocks in ideal magnetohydrodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Pullin, D. I. [Graduate Aerospace Laboratories, California Institute of Technology, Pasadena, California 91125 (United States); Mostert, W.; Wheatley, V. [School of Mechanical and Mining Engineering, University of Queensland, Queensland 4072 (Australia); Samtaney, R. [Mechanical Engineering, Physical Sciences and Engineering Division, King Abdullah University of Science and Technology, Thuwal (Saudi Arabia)

    2014-09-15

    We consider a cylindrically symmetrical shock converging onto an axis within the framework of ideal, compressible-gas non-dissipative magnetohydrodynamics (MHD). In cylindrical polar co-ordinates we restrict attention to either constant axial magnetic field or to the azimuthal but singular magnetic field produced by a line current on the axis. Under the constraint of zero normal magnetic field and zero tangential fluid speed at the shock, a set of restricted shock-jump conditions are obtained as functions of the shock Mach number, defined as the ratio of the local shock speed to the unique magnetohydrodynamic wave speed ahead of the shock, and also of a parameter measuring the local strength of the magnetic field. For the line current case, two approaches are explored and the results compared in detail. The first is geometrical shock-dynamics where the restricted shock-jump conditions are applied directly to the equation on the characteristic entering the shock from behind. This gives an ordinary-differential equation for the shock Mach number as a function of radius which is integrated numerically to provide profiles of the shock implosion. Also, analytic, asymptotic results are obtained for the shock trajectory at small radius. The second approach is direct numerical solution of the radially symmetric MHD equations using a shock-capturing method. For the axial magnetic field case the shock implosion is of the Guderley power-law type with exponent that is not affected by the presence of a finite magnetic field. For the axial current case, however, the presence of a tangential magnetic field ahead of the shock with strength inversely proportional to radius introduces a length scale R=√(μ{sub 0}/p{sub 0}) I/(2 π) where I is the current, μ{sub 0} is the permeability, and p{sub 0} is the pressure ahead of the shock. For shocks initiated at r ≫ R, shock convergence is first accompanied by shock strengthening as for the strictly gas-dynamic implosion. The

  7. Entropy jump across an inviscid shock wave

    Science.gov (United States)

    Salas, Manuel D.; Iollo, Angelo

    1995-01-01

    The shock jump conditions for the Euler equations in their primitive form are derived by using generalized functions. The shock profiles for specific volume, speed, and pressure are shown to be the same, however density has a different shock profile. Careful study of the equations that govern the entropy shows that the inviscid entropy profile has a local maximum within the shock layer. We demonstrate that because of this phenomenon, the entropy, propagation equation cannot be used as a conservation law.

  8. Collisionless Electrostatic Shock Modeling and Simulation

    Science.gov (United States)

    2016-10-21

    equations with piston -like boundary conditions gives a solution for the shock behavior. • Assumes cold upstream ions, therefore neglecting shock...temperature ratio (>10) – Wave Train Wavelength – Shock-Front Mach Number – Reflected Ion Beam Velocity Gathering Experiment Data – Double Plasma Device...experimental shock data. • Inconsistencies in published 1969 double -plasma device data hampered validation. Future Work: Extension to Moderately

  9. Shock waves in gas and plasma

    International Nuclear Information System (INIS)

    Niu, K.

    1996-01-01

    A shock wave is a discontinuous surface that connects supersonic flow with subsonic flow. After a shock wave, flow velocity is reduced, and pressure and temperature increase; entropy especially increases across a shock wave. Therefore, flow is in nonequilibrium, and irreversible processes occur inside the shock layer. The thickness of a shock wave in neutral gas is of the order of the mean free path of the fluid particle. A shock wave also appears in magnetized plasma. Provided that when the plasma flow is parallel to the magnetic field, a shock wave appears if the governing equation for velocity potential is in hyperbolic type in relation with the Mach number and the Alfven number. When the flow is perpendicular to the magnetic field, the Maxwell stress, in addition to the pressure, plays a role in the shock wave in plasma. When the plasma temperature is so high, as the plasma becomes collision-free, another type of shock wave appears. In a collision-free shock wave, gyromotions of electrons around the magnetic field lines cause the shock formation instead of collisions in a collision-dominant plasma or neutral gas. Regardless of a collision-dominant or collision-free shock wave, the fluid that passes through the shock wave is heated in addition to being compressed. In inertial confinement fusion, the fuel must be compressed. Really, implosion motion performs fuel compression. A shock wave, appearing in the process of implosion, compresses the fuel. The shock wave, however, heats the fuel more intensively, and it makes it difficult to compress the fuel further because high temperatures invite high pressure. Adiabatic compression of the fuel is the desired result during the implosion, without the formation of a shock wave. (Author)

  10. Electric shock and electrical fire specialty

    International Nuclear Information System (INIS)

    2011-02-01

    This book deals with electric shock and electrical fire, which is made up seven chapters. It describes of special measurement for electric shock and electrical fire. It mentions concretely about electrical fire analysis and precautionary measurement, electrical shock analysis cases, occurrence of static electricity and measurement, gas accident, analysis of equipment accident and precautionary measurement. The book is published to educate the measurement on electric shock and electrical fire by electrical safety technology education center in Korea Electrical Safety Corporation.

  11. Prenatal temperature shocks reduce cooperation

    NARCIS (Netherlands)

    Duchoslav, Jan

    2017-01-01

    Climate change has not only led to a sustained rise in mean global temperature over the past decades, but also increased the frequency of extreme weather events. This paper explores the effect of temperature shocks in utero on later-life taste for cooperation. Using historical climate data combined

  12. Shock Incarceration: Rehabilitation or Retribution?

    Science.gov (United States)

    MacKenzie, Doris Layton; And Others

    1989-01-01

    Reviews Louisiana's shock incarceration program used as alternative to standard prison incarceration. Program involves short period of imprisonment in a "boot camp" type atmosphere followed by three phases of intensive parole supervision. Examines the program in regard to its rehabilitative potential and compares program elements to…

  13. Shock Mounting for Heavy Machines

    Science.gov (United States)

    Thompson, A. R.

    1984-01-01

    Elastomeric bearings eliminate extraneous forces. Rocket thrust transmitted from motor to load cells via support that absorbs extraneous forces so they do not affect accuracy of thrust measurements. Adapter spoked cone fits over forward end of rocket motor. Shock mounting developed for rocket engines under test used as support for heavy machines, bridges, or towers.

  14. 2-Shock layered tuning campaign

    Science.gov (United States)

    Masse, Laurent; Dittrich, T.; Khan, S.; Kyrala, G.; Ma, T.; MacLaren, S.; Ralph, J.; Salmonson, J.; Tipton, R.; Los Alamos Natl Lab Team; Lawrence Livermore Natl Lab Team

    2016-10-01

    The 2-Shock platform has been developed to maintain shell sphericity throughout the compression phase of an indirect-drive target implosion and produce a stagnating hot spot in a quasi 1D-like manner. A sub-scale, 1700 _m outer diameter, and thick, 200 _m, uniformly Silicon doped, gas-filled plastic capsule is driven inside a nominal size 5750 _m diameter ignition hohlraum. The hohlraum fill is near vacuum to reduce back-scatter and improve laser/drive coupling. A two-shock pulse of about 1 MJ of laser energy drives the capsule. The thick capsule prevents ablation front feed-through to the imploded core. This platform has demonstrated its efficiency to tune a predictable and reproducible 1-D implosion with a nearly round shape. It has been shown that the high foot performance was dominated by the local defect growth due to the ablation front instability and by the hohlraum radiation asymmetries. The idea here is to take advantage of this 2-Shock platform to design a 1D-like layered implosion and eliminates the deleterious effects of radiation asymmetries and ablation front instability growth. We present the design work and our first experimental results of this near one-dimensional 2-Shock layered design. This work was performed under the auspices of the Lawrence Livermore National Security, LLC, (LLNS) under Contract No. DE-AC52-07NA27344.

  15. Interstellar turbulence and shock waves

    International Nuclear Information System (INIS)

    Bykov, A.M.

    1982-01-01

    Random deflections of shock fronts propagated through the turbulent interstellar medium can produce the strong electro-density fluctuations on scales l> or approx. =10 13 cm inferred from pulsar radio scintillations. The development of turbulence in the hot-phase ISM is discussed

  16. Nonlinearity, Conservation Law and Shocks

    Indian Academy of Sciences (India)

    However, genuine nonlinearity is always present in an ideal gas. The conservation form of the equation (25) brings in shocks which cut off the growing part of the amplitUde as shown in. Figure 15. Acknowledgements. The author sincerely thanks the two referees whose valuable comments led to an improvement of the ...

  17. Model for Shock Wave Chaos

    KAUST Repository

    Kasimov, Aslan R.

    2013-03-08

    We propose the following model equation, ut+1/2(u2−uus)x=f(x,us) that predicts chaotic shock waves, similar to those in detonations in chemically reacting mixtures. The equation is given on the half line, x<0, and the shock is located at x=0 for any t≥0. Here, us(t) is the shock state and the source term f is taken to mimic the chemical energy release in detonations. This equation retains the essential physics needed to reproduce many properties of detonations in gaseous reactive mixtures: steady traveling wave solutions, instability of such solutions, and the onset of chaos. Our model is the first (to our knowledge) to describe chaos in shock waves by a scalar first-order partial differential equation. The chaos arises in the equation thanks to an interplay between the nonlinearity of the inviscid Burgers equation and a novel forcing term that is nonlocal in nature and has deep physical roots in reactive Euler equations.

  18. EXTRACORPOREAL SHOCK WAVE LITHOTRIPSY AS ...

    African Journals Online (AJOL)

    Objective To evaluate extracorporeal shock wave lithotripsy (ESWL) as a monotherapy for urolithiasis in patients with solitary kidney and to determine the factors that may affect its results. Patients and Methods Using the Dornier MFL 5000 lithotriptor, 106 patients with solitary kidney (80 men and 26 women) were treated for ...

  19. Shock formation within sonoluminescence bubbles

    International Nuclear Information System (INIS)

    Vuong, V.Q.; Szeri, A.J.; Young, D.A.

    1999-01-01

    A strong case has been made by several authors that sharp, spherically symmetric shocks converging on the center of a spherical bubble driven by a strong acoustic field give rise to rapid compression and heating that produces the brief flash of light known as sonoluminescence. The formation of such shocks is considered. It is found that, although at the main collapse the bubble wall does indeed launch an inwardly-traveling compression wave, and although the subsequent reflection of the wave at the bubble center produces a very rapid temperature peak, the wave is prevented from steepening into a sharp shock by an adverse gradient in the sound speed caused by heat transfer. It is shown that the mathematical characteristics of the flow can be prevented from accumulating into a shock front by this adverse sound speed gradient. A range of results is presented for a variety of bubble ambient radii and sound field amplitudes suggested by experiments. The time scale of the peak temperature in the bubble is set by the dynamics of the compression wave: this is typically in the range 100 - 300 ps (FWHM) in concert with recent measurements of the sonoluminescence pulse width. copyright 1999 American Institute of Physics

  20. Model for Shock Wave Chaos

    KAUST Repository

    Kasimov, Aslan R.; Faria, Luiz; Rosales, Rodolfo R.

    2013-01-01

    : steady traveling wave solutions, instability of such solutions, and the onset of chaos. Our model is the first (to our knowledge) to describe chaos in shock waves by a scalar first-order partial differential equation. The chaos arises in the equation

  1. Studying shocks in model astrophysical flows

    International Nuclear Information System (INIS)

    Chakrabarti, S.K.

    1989-01-01

    We briefly discuss some properties of the shocks in the existing models for quasi two-dimensional astrophysical flows. All of these models which allow the study of shock analytically have some unphysical characteristics due to inherent assumptions made. We propose a hybrid model for a thin flow which has fewer unpleasant features and is suitable for the study of shocks. (author). 5 refs

  2. Shock waves in relativistic nuclear matter, I

    International Nuclear Information System (INIS)

    Gleeson, A.M.; Raha, S.

    1979-02-01

    The relativistic Rankine-Hugoniot relations are developed for a 3-dimensional plane shock and a 3-dimensional oblique shock. Using these discontinuity relations together with various equations of state for nuclear matter, the temperatures and the compressibilities attainable by shock compression for a wide range of laboratory kinetic energy of the projectile are calculated. 12 references

  3. The microphysics of collisionless shock waves

    DEFF Research Database (Denmark)

    Marcowith, Alexandre; Bret, Antoine; Bykov, Andrei

    2016-01-01

    Collisionless shocks, that is shocks mediated by electromagnetic processes, are customary in space physics and in astrophysics. They are to be found in a great variety of objects and environments: magnetospheric and heliospheric shocks, supernova remnants, pulsar winds and their nebulæ, active ga...

  4. Impulsivity, aggression and brain structure in high and low lethality suicide attempters with borderline personality disorder.

    Science.gov (United States)

    Soloff, Paul; White, Richard; Diwadkar, Vaibhav A

    2014-06-30

    Impulsivity and aggressiveness are trait dispositions associated with the vulnerability to suicidal behavior across diagnoses. They are associated with structural and functional abnormalities in brain networks involved in regulation of mood, impulse and behavior. They are also core characteristics of borderline personality disorder (BPD), a disorder defined, in part, by recurrent suicidal behavior. We assessed the relationships between personality traits, brain structure and lethality of suicide attempts in 51 BPD attempters using multiple regression analyses on structural MRI data. BPD was diagnosed by the Diagnostic Interview for Borderline Patients-revised, impulsivity by the Barratt Impulsiveness Scale (BIS), aggression by the Brown-Goodwin Lifetime History of Aggression (LHA), and high lethality by a score of 4 or more on the Lethality Rating Scale (LRS). Sixteen High Lethality attempters were compared to 35 Low Lethality attempters, with no significant differences noted in gender, co-morbidity, childhood abuse, BIS or LHA scores. Degree of medical lethality (LRS) was negatively related to gray matter volumes across multiple fronto-temporal-limbic regions. Effects of impulsivity and aggression on gray matter volumes discriminated High from Low Lethality attempters and differed markedly within lethality groups. Lethality of suicide attempts in BPD may be related to the mediation of these personality traits by specific neural networks. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  5. Heterochromatin position effects on circularized sex chromosomes cause filicidal embryonic lethality in Drosophila melanogaster.

    Science.gov (United States)

    Ferree, Patrick M; Gomez, Karina; Rominger, Peter; Howard, Dagnie; Kornfeld, Hannah; Barbash, Daniel A

    2014-04-01

    Some circularized X-Y chromosomes in Drosophila melanogaster are mitotically unstable and induce early embryonic lethality, but the genetic basis is unknown. Our experiments suggest that a large region of X-linked satellite DNA causes anaphase bridges and lethality when placed into a new heterochromatic environment within certain circularized X-Y chromosomes. These results reveal that repetitive sequences can be incompatible with one another in cis. The lethal phenotype also bears a remarkable resemblance to a case of interspecific hybrid lethality.

  6. Late radiation effects in animals surviving lethal irradiation

    International Nuclear Information System (INIS)

    Dimitrov, L.A.

    1974-01-01

    Animals (rats, mice, dogs) survived lethal irradiation by means of prophylactic-therapeutic treatments or previously irradiated, were studied for late radiation effects: life span, cachexia and fat growing of hypophysical type, tissue or organ hypoplasia manifested by disturbed hemopoiesis, suppressed function of adrenal gland, etc., suppressed immune reactivity of the irradiated organism, atypical biochemical changes in DNA and protein metabolism, epilation, chronic dermatitis, ulcerations, reduced reproductivity or full sterility, damage of kidneys leading to nephrosclerosis, dishormonal states, cataracts, diffuse sclerotic processes, various kinds of malignant and non-malignant tumors. In these cases hemopoiesis compensated for a definite time peripheral blood composition, but during the late period it showed features of incompleteness: shorter life survival of erythrocytes and thrombocytes manifested by a decreased binding of labelled methionine in these blood elements, anemia and relative thrombocytopenia sometimes with an increased number of polychromatic erythrocytes in peripheral blood and a decreased number of reticulocytes at the same time; lymphopenia and relative leucopenia with an increased number of hypersegmented neutrophils. Decreased reproductivity and atypical biochemical changes available in the first generation of the irradiated animals showed the probable role of mutagenic factors in the emergence of some late radiation effects. A significant part of late radiation sequences were due to neuro-endocrine desintegrations which lead to a disturbed supply of the vessels and afterwards to their sclerosis. Some of the described late radiation effects were also observed in biological controls as festures of ageing while in irradiated animals they were manifested in an earlier period. After application of optimal amounts radioprotectors (AET, cysteamine, serotonin) a more marked protective effect is demonstrated in the early reactions (time survival

  7. Permeability enhancement by shock cooling

    Science.gov (United States)

    Griffiths, Luke; Heap, Michael; Reuschlé, Thierry; Baud, Patrick; Schmittbuhl, Jean

    2015-04-01

    The permeability of an efficient reservoir, e.g. a geothermal reservoir, should be sufficient to permit the circulation of fluids. Generally speaking, permeability decreases over the life cycle of the geothermal system. As a result, is usually necessary to artificially maintain and enhance the natural permeability of these systems. One of the methods of enhancement -- studied here -- is thermal stimulation (injecting cold water at low pressure). This goal of this method is to encourage new thermal cracks within the reservoir host rocks, thereby increasing reservoir permeability. To investigate the development of thermal microcracking in the laboratory we selected two granites: a fine-grained (Garibaldi Grey granite, grain size = 0.5 mm) and a course-grained granite (Lanhelin granite, grain size = 2 mm). Both granites have an initial porosity of about 1%. Our samples were heated to a range of temperatures (100-1000 °C) and were either cooled slowly (1 °C/min) or shock cooled (100 °C/s). A systematic microstructural (2D crack area density, using standard stereological techniques, and 3D BET specific surface area measurements) and rock physical property (porosity, P-wave velocity, uniaxial compressive strength, and permeability) analysis was undertaken to understand the influence of slow and shock cooling on our reservoir granites. Microstructurally, we observe that the 2D crack surface area per unit volume and the specific surface area increase as a result of thermal stressing, and, for the same maximum temperature, crack surface area is higher in the shock cooled samples. This observation is echoed by our rock physical property measurements: we see greater changes for the shock cooled samples. We can conclude that shock cooling is an extremely efficient method of generating thermal microcracks and modifying rock physical properties. Our study highlights that thermal treatments are likely to be an efficient method for the "matrix" permeability enhancement of

  8. Gastrointestinal decontamination in healthy and lethally irradiated monkeys

    International Nuclear Information System (INIS)

    Hendriks, W.D.H.

    1980-01-01

    In periods of extreme immunosuppression, infections which are often life-threatening, frequently occur. In an attempt to prevent such infections in lethally irradiated rhesus monkeys, the animals were subjected to strict reverse isolation prior to irradiation and administrated orally with nonabsorbable antibiotics in order to eliminate their microflora. The antibiotic combination was selected on the basis of a sensitivity test and was added to the liquid food supply. To rapidly achieve a high bactericidal concentration in the intestine, the same antibiotics were additionally given orally for 5 days. The microflora was reduced rapidly; within a few days sterile cultures were obtained. Particularly after discontinuation of the administration of the additional antibiotics were colonizations found. In contrast to colonizations persisting from the first day of treatment on, the first were rather easy to suppress. (Auth.)

  9. In vitro cell culture lethal dose submitted to gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Moreno, Carolina S.; Rogero, Sizue O.; Rogero, Jose Roberto [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)], e-mail: carolina_sm@hotmail.com; Ikeda, Tamiko I.; Cruz, Aurea S. [Instituto Adolfo Lutz, Sao Paulo, SP (Brazil)

    2009-07-01

    The present study was designed to evaluate the in vitro effect of gamma radiation in cell culture of mouse connective tissue exposed to different doses of gamma radiation and under several conditions. The cell viability was analyzed by neutral red uptake methodology. This assay was developed for establish a methodology to be used in the future in the study of resveratrol radioprotection. Resveratrol (3,4',5- trihydroxystilbene), a phenolic phytoalexin that occurs naturally in some spermatophytes, such as grapevines, in response to injury as fungal infections and exposure to ultraviolet light. In the wines this compound is found at high levels and is considered one of the highest antioxidant constituents. The intense antioxidant potential of resveratrol provides many pharmacological activities including cardioprotection, chemoprevention and anti-tumor effects. Our results demonstrated that {sup 60}Co gamma radiation lethal dose (LD50) on NCTC clone 929 cells was about 340Gy. (author)

  10. In vitro cell culture lethal dose submitted to gamma radiation

    International Nuclear Information System (INIS)

    Moreno, Carolina S.; Rogero, Sizue O.; Rogero, Jose Roberto; Ikeda, Tamiko I.; Cruz, Aurea S.

    2009-01-01

    The present study was designed to evaluate the in vitro effect of gamma radiation in cell culture of mouse connective tissue exposed to different doses of gamma radiation and under several conditions. The cell viability was analyzed by neutral red uptake methodology. This assay was developed for establish a methodology to be used in the future in the study of resveratrol radioprotection. Resveratrol (3,4',5- trihydroxystilbene), a phenolic phytoalexin that occurs naturally in some spermatophytes, such as grapevines, in response to injury as fungal infections and exposure to ultraviolet light. In the wines this compound is found at high levels and is considered one of the highest antioxidant constituents. The intense antioxidant potential of resveratrol provides many pharmacological activities including cardioprotection, chemoprevention and anti-tumor effects. Our results demonstrated that 60 Co gamma radiation lethal dose (LD50) on NCTC clone 929 cells was about 340Gy. (author)

  11. Perinatally lethal short rib-polydactyly syndromes. Pt. 1

    International Nuclear Information System (INIS)

    Sillence, D.; Kozlowski, K.; Bar-ziv, J.; Fuhrmann-Rieger, A.; Fuhrmann, W.; Pascu, F.

    1987-01-01

    Thirteen newborns with lethal short rib-polydactyly (SRP) have been reviewed, 11 with SRP type 3 (Verma-Naumoff) and 2 with SRP tye 2 (Majewski). In the former group there were three sets of siblings. The excess of males with SRP type III (Verma-Naumoff) is confirmed in this present study. A high frequency of phenotypic females including sex-reversed constitutional males with SRP type 1 (Saldino-Noonan) is in marked contrast to these findings in SRP type 3. Possible hypotheses include variable expressivity in non-Majewski short rib-polydactyly syndromes with sex-reversed and constitutional female cases tending to show more severe phenotypic expression both in terms of major anomalies and skeletal dysplastic effects. (orig.)

  12. Lethal carbon monoxide toxicity in a concrete shower unit.

    Science.gov (United States)

    Heath, Karen; Byard, Roger W

    2018-05-23

    A 47-year-old previously-well woman was found dead on the floor of a shower cubicle on a property in rural South Australia. The impression of the attending doctor and police was of collapse due to natural disease. Although there was significant stenosing coronary artery atherosclerosis found at autopsy, cherry pink discoloration of tissues prompted measurement of the blood carboxyhemoglobin level which was found to be 55%. The source of the gas was a poorly-maintained hot water heater that was mounted on the inside wall of the shower. Construction of the shower using an impermeable concrete rain water tank had caused gas accumulation when the water heater malfunctioned. Had lethal carbon monoxide exposure not been identified others using the same shower unit would also have been at risk.

  13. Analysis of Lethality and Malformations During Zebrafish (Danio rerio) Development.

    Science.gov (United States)

    Raghunath, Azhwar; Perumal, Ekambaram

    2018-01-01

    The versatility offered by zebrafish (Danio rerio) makes it a powerful and an attractive vertebrate model in developmental toxicity and teratogenicity assays. Apart from the newly introduced chemicals as drugs, xenobiotics also induce abnormal developmental abnormalities and congenital malformations in living organisms. Over the recent decades, zebrafish embryo/larva has emerged as a potential tool to test teratogenicity potential of these chemicals. Zebrafish responds to compounds as mammals do as they share similarities in their development, metabolism, physiology, and signaling pathways with that of mammals. The methodology used by the different scientists varies enormously in the zebrafish embryotoxicity test. In this chapter, we present methods to assess lethality and malformations during zebrafish development. We propose two major malformations scoring systems: binomial and relative morphological scoring systems to assess the malformations in zebrafish embryos/larvae. Based on the scoring of the malformations, the test compound can be classified as a teratogen or a nonteratogen and its teratogenic potential is evaluated.

  14. BRINE SHRIMP LETHALITY BIOASSAY OF GLAUCIUM GRANDIFLORUM VAR. GRANDIFLORUM

    OpenAIRE

    A. SARI, Ç. ÜNSAL, İ. SARIOĞLU, A. SARI, Ç. ÜNSAL, İ. SARIOĞLU

    2013-01-01

    Türkiye'nin 3 farklı bölgesinden toplanan Glaucium grandiflorum Boiss. et Huet var. grandiflorum örneklerinin toprak üstü kısımlarından elde edilen alkaloit ekstreleri ve bu ekstrelerden elde edilen majör alkaloitler allokriptopin, protopİn, (+)-izokoridin, (+)-korİdin üzerinde brİne shrimp lethality testi yapılarak sitotoksisiteleri İncelenmiştir. Glaucium grandiflorum var. grandiflorum türünün 3 örneği de önemli oranda sitotoksik aktİvite göstermiştir. Allokriptopin, protopin, (+)-izok...

  15. Mechanisms of Lethal Cerebrovascular Accidents in Turner Syndrome.

    Science.gov (United States)

    Byard, Roger W

    2016-05-01

    A case of intracerebral hemorrhage in Turner syndrome is reported with an analysis of possible causes of cerebrovascular accidents in this condition. A 42-year-old woman with known Turner syndrome died soon after hospital admission having been found unconscious at her home address. At autopsy, she showed typical features of Turner syndrome with short stature, webbing of the neck, underdeveloped breasts, and an increased carrying angle of the arm. Death was due to a large left-sided intracerebral hemorrhage extending from the left basal ganglia into the white matter of the frontal lobe and lateral ventricle. Cases of unexpected death in Turner syndrome may arise from occult cerebrovascular accidents which may be hemorrhagic or nonhemorrhagic. Associated features include hypertension, vascular malformations, accelerated atherogenesis, cystic medial necrosis, and moyamoya syndrome. The possibility of Turner syndrome should be considered in cases where there has been a lethal cerebrovascular event in a younger woman. © 2016 American Academy of Forensic Sciences.

  16. Preliminary results on epidemiology of Coconut Lethal Yellowing in Ghana

    Directory of Open Access Journals (Sweden)

    Bonnot François

    2009-03-01

    Full Text Available Epidemiological studies are of major importance in understanding the determinants of plant diseases in order to control the risks of their spreading. A research programme on the epidemiology of coconut lethal yellowing, or Cape Saint Paul Wilt Disease (CSPWD, in Ghana was launched in March 2007. The objective was to characterize the distribution and spread of the disease in space and time at various scales, and their relation with the environment. This article presents the general strategy used to evaluate the incidence of CSPWD along with the environmental, ecological and agronomical variables at regional level. A survey was undertaken on 1,166 plots of Coconut Sector Development Project (CSDP planted with Malayan Yellow Dwarf (MYD × Vanuatu Tall (VTT hybrids in Western Region and Central Region. Preliminary results on the distribution of CSPWD and outside variables at regional scale, along with their relations, are given.

  17. Thyroid and pancreatic hormones in lethally irradiated rats

    International Nuclear Information System (INIS)

    Ahlersova, E.; Ahlers, I.; Praslicka, M.

    1985-01-01

    The concentrations of thyroxine, triiodothyronine and reverse triiodothyronine, glucagon and insulin in the serum or plasma were determined by radioimmunoassay in male rats of the Wistar strain 1, 6, 24, 48 and 72 hours after irradiation with 14.35 Gy (1500R) of X-rays. The irradiated and sham-irradiated rats were starved till examination. The concentrations of thyroxine and triiodothyronine dropped 6 hours after irradiation as compared with controls, the concentration of thyroxine also dropped after 72 hours. The level of reverse triiodothyronine in irradiated rats increased in the terminal period. The level of insulin dropped 24 hours after irradiation, at 72 hours it was higher than that in controls. The concentration of glucagon in irradiated rats increased in the terminal phase of radiation disease. The results document the diverse reaction of hormones in lethally irradiated rats and contribute to a deeper recognition of metabolic imbalance in the course of radiation disease. (author)

  18. Lethal midline granuloma histologically. Management with radiation therapy

    International Nuclear Information System (INIS)

    Barriga T, L.; Misad, O.; Moscol, A.; Pinillos G, L.; Barriga T, O.; Heredia, A.; Pinillos A, L.; Mayer Z, T.

    1995-01-01

    From 1973 through 1990, 24 patients with lethal midline granuloma histologically demonstrated were treated with radiation therapy at the Radiation Oncology Department of the National Institute of Neoplasmic Diseases from Peru. The authors reports the results of their experience, reviewed the literature and present a clinic and pathologic discussion of this rare entity. All the patients received radiotherapy as the main treatment and 12 of them received chemotherapy. The male to female ratio was 5:3 with a mean age of 29.33 years (range 6 to 84 years old). Symptoms of nasal obstruction were presented 45.83%, nasal enlargement in 33.33%, nasal discharge in 29.16% and fever in 29.16%, principally. We believe that radiotherapy is the treatment of choice in this report we can not demonstrate it because of the small number of patients. (authors). 28 refs., 10 tabs

  19. Evaluation of Lethal Giant Larvae as a Schistosomiasis Vaccine Candidate

    Directory of Open Access Journals (Sweden)

    Yufan Cao

    2016-01-01

    Full Text Available Schistosomiasis is a neglected tropical disease of humans, and it is considered to be the second most devastating parasitic disease after malaria. Eggs produced by normally developed female worms are important in the transmission of the parasite, and they responsible for the pathogenesis of schistosomiasis. The tumor suppressor gene lethal giant larvae (lgl has an essential function in establishing apical-basal cell polarity, cell proliferation, differentiation, and tissue organization. In our earlier study, downregulation of the lgl gene induced a significant reduction in the egg hatching rate of Schistosoma japonicum (Sj eggs. In this study, the Sjlgl gene was used as a vaccine candidate against schistosomiasis, and vaccination achieved and maintained a stable reduction of the egg hatching rate, which is consistent with previous studies, in addition to reducing the worm burden and liver egg burden in some trials.

  20. Radiation-induced mutagenicity and lethality in Salmonella typhimurium

    International Nuclear Information System (INIS)

    Isildar, M.; Bakale, G.

    1983-01-01

    The mutagenic and lethal effects of ionizing radiation on histidine-deficient auxotrophs of Salmonella typhimurium were studied to improve the understanding of radiation damage to DNA. The auxotrophs were divided into two groups - one which is sensitive to base-pair substitutions and another sensitive to frameshifts. These groups were composed of parent-daughter pairs in which the chemical mutagenicity enhancing plasmid, pKM101, is absent in the parent strain and present in the daughter. Co-60 #betta#-radiation and 250 kV x-rays were used to irradiate the bacteria. Irradiation of the frameshift - sensitive strains which carry the pKm101 plasmid doubled the absolute number of induced revertants whereas irradiation of the base-pair substitution sensitive strain which also carries the pKm101 plasmid produced nearly no change in the number of induced revertants. A nearly negligible effect on the mutation rate was observed for all parent strains

  1. Late radiation effects in animals surviving lethal irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Dimitrov, L A

    1974-01-01

    Animals (rats, mice, dogs) survived lethal irradiation by means of prophylactic-therapeutic treatments or previously irradiated, were studied for late radiation effects: life span, cachexia and fat growing of hypophysical type, tissue or organ hypoplasia manifested by disturbed hemopoiesis, suppressed function of adrenal gland, etc., suppressed immune reactivity of the irradiated organism, atypical biochemical changes in DNA and protein metabolism, epilation, chronic dermatitis, ulcerations, reduced reproductivity or full sterility, damage of kidneys leading to nephrosclerosis, dishormonal states, cataracts, diffuse sclerotic processes, various kinds of malignant and non-malignant tumors. In these cases hemopoiesis compensated for a definite time peripheral blood composition, but during the late period it showed features of incompleteness: shorter life survival of erythrocytes and thrombocytes manifested by a decreased binding of labelled methionine in these blood elements, anemia and relative thrombocytopenia sometimes with an increased number of polychromatic erythrocytes in peripheral blood and a decreased number of reticulocytes at the same time; lymphopenia and relative leucopenia with an increased number of hypersegmented neutrophils. Decreased reproductivity and atypical biochemical changes available in the first generation of the irradiated animals showed the probable role of mutagenic factors in the emergency of some late radiation effects. A significant part of late radiation sequences were due to neuro-endocrine disintegrations. Some of the described late radiation effects were also observed in biological controls as features of ageing. After application of radioprotectors (AET, cysteamine, serotonin) a more marked protective effect is demonstrated in the early reactions (time survival till 30th day, DNA and protein metabolism, immune reactions) of the lethally irradiated animals.

  2. Inappropriate shocks in the subcutaneous ICD

    DEFF Research Database (Denmark)

    Olde Nordkamp, Louise R A; Brouwer, Tom F; Barr, Craig

    2015-01-01

    shocks have been reported. METHODS: We analyzed the incidence, predictors and management of inappropriate shocks in the EFFORTLESS S-ICD Registry, which collects S-ICD implantation information and follow-up data from clinical centers in Europe and New Zealand. RESULTS: During a follow-up of 21 ± 13...... xyphoid to V6) reduced the risk. Reprogramming or optimization of SVT treatment after the first clinical event of inappropriate shock was successful in preventing further inappropriate shocks for cardiac oversensing and SVT events. CONCLUSIONS: Inappropriate shocks, mainly due to cardiac oversensing...

  3. Pulmonary heat shock protein expression after exposure to a metabolically activated Clara cell toxicant: relationship to protein adduct formation

    International Nuclear Information System (INIS)

    Williams, Kurt J.; Cruikshank, Michael K.; Plopper, Charles G.

    2003-01-01

    Heat shock proteins/stress proteins (Hsps) participate in regulation of protein synthesis and degradation and serve as general cytoprotectants, yet their role in lethal Clara cell injury is not clear. To define the pattern of Hsp expression in acute lethal Clara cell injury, mice were treated with the Clara cell-specific toxicant naphthalene (NA), and patterns of expression compared to electrophilic protein adduction and previously established organellar degradation and gluathione (GSH) depletion. In sites of lethal injury (distal bronchiole), prior to organellar degradation (1 h post-NA), protein adduction is detectable and ubiquitin, Hsp 25, Hsp 72, and heme-oxygenase 1 (HO-1) are increased. Maximal Hsp expression, protein adduction, and GSH depletion occur simultaneous (by 2-3 h) with early organelle disruption. Hsp expression is higher later (6-24 h), only in exfoliating cells. In airway sites (proximal bronchiole) with nonlethal Clara cell injury elevation of Hsp 25, 72, and HO-1 expression follows significant GSH depletion (greater than 50% 2 h post-NA). This data build upon our previous studies and we conclude that (1) in lethal (terminal bronchiole) and nonlethal (proximal bronchiole) Clara cell injury, Hsp induction is associated with the loss of GSH and increased protein adduction, and (2) in these same sites, organelle disruption is not a prerequisite for Hsp induction

  4. Evaluating the lethal and pre-lethal effects of a range of fungi against adult Anopheles stephensi mosquitoes

    Directory of Open Access Journals (Sweden)

    Blanford Simon

    2012-11-01

    Full Text Available Abstract Background Insecticide resistance is seriously undermining efforts to eliminate malaria. In response, research on alternatives to the use of chemical insecticides against adult mosquito vectors has been increasing. Fungal entomopathogens formulated as biopesticides have received much attention and have shown considerable potential. This research has necessarily focused on relatively few fungal isolates in order to ‘prove concept’. Further, most attention has been paid to examining fungal virulence (lethality and not the other properties of fungal infection that might also contribute to reducing transmission potential. Here, a range of fungal isolates were screened to examine variation in virulence and how this relates to additional pre-lethal reductions in feeding propensity. Methods The Asian malaria vector, Anopheles stephensi was exposed to 17 different isolates of entomopathogenic fungi belonging to species of Beauveria bassiana, Metarhizium anisopliae, Metarhizium acridum and Isaria farinosus. Each isolate was applied to a test substrate at a standard dose rate of 1×109 spores ml-1 and the mosquitoes exposed for six hours. Subsequently the insects were removed to mesh cages where survival was monitored over the next 14 days. During this incubation period the mosquitoes’ propensity to feed was assayed for each isolate by offering a feeding stimulant at the side of the cage and recording the number probing. Results and conclusions Fungal isolates showed a range of virulence to A. stephensi with some causing >80% mortality within 7 days, while others caused little increase in mortality relative to controls over the study period. Similarly, some isolates had a large impact on feeding propensity, causing >50% pre-lethal reductions in feeding rate, whereas other isolates had very little impact. There was clear correlation between fungal virulence and feeding reduction with virulence explaining nearly 70% of the variation in

  5. Perpendicular relativistic shocks in magnetized pair plasma

    Science.gov (United States)

    Plotnikov, Illya; Grassi, Anna; Grech, Mickael

    2018-04-01

    Perpendicular relativistic (γ0 = 10) shocks in magnetized pair plasmas are investigated using two dimensional Particle-in-Cell simulations. A systematic survey, from unmagnetized to strongly magnetized shocks, is presented accurately capturing the transition from Weibel-mediated to magnetic-reflection-shaped shocks. This transition is found to occur for upstream flow magnetizations 10-3 10-2, it leaves place to a purely electromagnetic precursor following from the strong emission of electromagnetic waves at the shock front. Particle acceleration is found to be efficient in weakly magnetized perpendicular shocks in agreement with previous works, and is fully suppressed for σ > 10-2. Diffusive Shock Acceleration is observed only in weakly magnetized shocks, while a dominant contribution of Shock Drift Acceleration is evidenced at intermediate magnetizations. The spatial diffusion coefficients are extracted from the simulations allowing for a deeper insight into the self-consistent particle kinematics and scale with the square of the particle energy in weakly magnetized shocks. These results have implications for particle acceleration in the internal shocks of AGN jets and in the termination shocks of Pulsar Wind Nebulae.

  6. Initial conditions of radiative shock experiments

    International Nuclear Information System (INIS)

    Kuranz, C. C.; Drake, R. P.; Krauland, C. M.; Marion, D. C.; Grosskopf, M. J.; Rutter, E.; Torralva, B.; Holloway, J. P.; Bingham, D.; Goh, J.; Boehly, T. R.; Sorce, A. T.

    2013-01-01

    We performed experiments at the Omega Laser Facility to characterize the initial, laser-driven state of a radiative shock experiment. These experiments aimed to measure the shock breakout time from a thin, laser-irradiated Be disk. The data are then used to inform a range of valid model parameters, such as electron flux limiter and polytropic γ, used when simulating radiative shock experiments using radiation hydrodynamics codes. The characterization experiment and the radiative shock experiment use a laser irradiance of ∼7 × 10 14 W cm −2 to launch a shock in the Be disk. A velocity interferometer and a streaked optical pyrometer were used to infer the amount of time for the shock to move through the Be disk. The experimental results were compared with simulation results from the Hyades code, which can be used to model the initial conditions of a radiative shock system using the CRASH code

  7. Exploratory laser-driven shock wave studies

    International Nuclear Information System (INIS)

    Solem, J.C.; Veeser, L.R.

    1977-11-01

    We show the results of a feasibility study for investigating shock structure and for measuring equation-of-state parameters using high-energy, short-pulse lasers. We discuss the temporal and spatial structure of the luminosity from laser-driven shock unloading in aluminum foils. We demonstrate that shock velocity can be measured by observing the time interval between shock emergence across two thicknesses and show data for shocks of 1.3 and 2.1 Mbar. The fact that we observe shock fronts cleanly breaking through steps as small as 3 μm indicates that the shock front thickness is very small in the few megabar region; this is the first experimental verification that these fronts are not more than a few micrometers thick. We present approximate measurements of free-surface velocity. Finally, we speculate on the use of these techniques to obtain detailed equation-of-state data

  8. Shock-induced chemistry in organic materials

    Energy Technology Data Exchange (ETDEWEB)

    Dattelbaum, Dana M [Los Alamos National Laboratory; Sheffield, Steve [Los Alamos National Laboratory; Engelke, Ray [Los Alamos National Laboratory; Manner, Virginia [Los Alamos National Laboratory; Chellappa, Raja [Los Alamos National Laboratory; Yoo, Choong - Shik [WASHINGTON STATE UNIV

    2011-01-20

    The combined 'extreme' environments of high pressure, temperature, and strain rates, encountered under shock loading, offer enormous potential for the discovery of new paradigms in chemical reactivity not possible under more benign conditions. All organic materials are expected to react under these conditions, yet we currently understand very little about the first bond-breaking steps behind the shock front, such as in the shock initiation of explosives, or shock-induced reactivity of other relevant materials. Here, I will present recent experimental results of shock-induced chemistry in a variety of organic materials under sustained shock conditions. A comparison between the reactivity of different structures is given, and a perspective on the kinetics of reaction completion under shock drives.

  9. Experimental methods of shock wave research

    CERN Document Server

    Seiler, Friedrich

    2016-01-01

    This comprehensive and carefully edited volume presents a variety of experimental methods used in Shock Waves research. In 14 self contained chapters this 9th volume of the “Shock Wave Science and Technology Reference Library” presents the experimental methods used in Shock Tubes, Shock Tunnels and Expansion Tubes facilities. Also described is their set-up and operation. The uses of an arc heated wind tunnel and a gun tunnel are also contained in this volume. Whenever possible, in addition to the technical description some typical scientific results obtained using such facilities are described. Additionally, this authoritative book includes techniques for measuring physical properties of blast waves and laser generated shock waves. Information about active shock wave laboratories at different locations around the world that are not described in the chapters herein is given in the Appendix, making this book useful for every researcher involved in shock/blast wave phenomena.

  10. Motion of shocks through interplanetary streams

    International Nuclear Information System (INIS)

    Burlaga, L.F.; Scudder, J.D.

    1975-01-01

    A model for the motion of flare-generated shocks through interplanetary streams is presented, illustrating the effects of a stream-shock interaction on the shock strength and geometry. It is a gas dynamic calculation based on Whitham's method and on an empirical approximation for the relevant characteristics of streams. The results show that the Mach number of a shock can decrease appreciably to near unity in the interaction region ahead of streams and that the interaction of a spherically symmetric shock with a spiral-shaped corotating stream can cause significant distortions of the initial shock front geometry. The geometry of the February 15--16, 1967, shock discussed by Lepping and Chao (1972) is qualitatively explained by this model

  11. Do oil shocks predict economic policy uncertainty?

    Science.gov (United States)

    Rehman, Mobeen Ur

    2018-05-01

    Oil price fluctuations have influential role in global economic policies for developed as well as emerging countries. I investigate the role of international oil prices disintegrated into structural (i) oil supply shock, (ii) aggregate demand shock and (iii) oil market specific demand shocks, based on the work of Kilian (2009) using structural VAR framework on economic policies uncertainty of sampled markets. Economic policy uncertainty, due to its non-linear behavior is modeled in a regime switching framework with disintegrated structural oil shocks. Our results highlight that Indian, Spain and Japanese economic policy uncertainty responds to the global oil price shocks, however aggregate demand shocks fail to induce any change. Oil specific demand shocks are significant only for China and India in high volatility state.

  12. Shock Wave Dynamics in Weakly Ionized Plasmas

    Science.gov (United States)

    Johnson, Joseph A., III

    1999-01-01

    An investigation of the dynamics of shock waves in weakly ionized argon plasmas has been performed using a pressure ruptured shock tube. The velocity of the shock is observed to increase when the shock traverses the plasma. The observed increases cannot be accounted for by thermal effects alone. Possible mechanisms that could explain the anomalous behavior include a vibrational/translational relaxation in the nonequilibrium plasma, electron diffusion across the shock front resulting from high electron mobility, and the propagation of ion-acoustic waves generated at the shock front. Using a turbulence model based on reduced kinetic theory, analysis of the observed results suggest a role for turbulence in anomalous shock dynamics in weakly ionized media and plasma-induced hypersonic drag reduction.

  13. Study on Reflected Shock Wave/Boundary Layer Interaction in a Shock Tube

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dong Wook; Kim, Tae Ho; Kim, Heuy Dong [Andong Nat’l Univ., Andong (Korea, Republic of)

    2017-07-15

    The interaction between a shock wave and a boundary layer causes boundary layer separation, shock train, and in some cases, strong unsteadiness in the flow field. Such a situation is also observed in a shock tube, where the reflected shock wave interacts with the unsteady boundary layer. However, only a few studies have been conducted to investigate the shock train phenomenon in a shock tube. In the present study, numerical studies were conducted using the two-dimensional axisymmetric domain of a shock tube, and compressible Navier-Stokes equations were solved to clarify the flow characteristics of shock train phenomenon inside a shock tube. A detailed wave diagram was developed based on the present computational results, which were validated with existing experimental data.

  14. Insight into magnetorheological shock absorbers

    CERN Document Server

    Gołdasz, Janusz

    2015-01-01

    This book deals with magnetorheological fluid theory, modeling and applications of automotive magnetorheological dampers. On the theoretical side a review of MR fluid compositions and key factors affecting the characteristics of these fluids is followed by a description of existing applications in the area of vibration isolation and flow-mode shock absorbers in particular. As a majority of existing magnetorheological devices operates in a so-called flow mode a critical review is carried out in that regard. Specifically, the authors highlight common configurations of flow-mode magnetorheological shock absorbers, or so-called MR dampers that have been considered by the automotive industry for controlled chassis applications. The authors focus on single-tube dampers utilizing a piston assembly with one coil or multiple coils and at least one annular flow channel in the piston.

  15. Magnetohydrodynamic shocks in molecular clouds

    International Nuclear Information System (INIS)

    Chernoff, D.F.

    1985-01-01

    Part one develops the mathematical and physical theory of one-dimensional, time-independent subalfvenic flow in partially ionized gas with magnetic fields, for application to shocks in molecular clouds. Unlike normal gas-dynamic shocks, the neutral flow may be continuous and cool if the gas radiates efficiently and does not self-ionize. Analytic solutions are given in the limit that the neutral gas is either adiabatic or isothermal (cold). Numerical techniques are developed and applied to find the neutral flow under general circumstances. Part two extends the theory and results of part one in three ways: (1) to faster, superalfvenic flow, (2) to complex gases containing heavy charged particles (grains) in addition to ions, containing heavy charged particles (grains) in addition to ions, electrons and neutrals, and (3) to the entire range in (Omega tau), the ratio of charged particle damping time to gyroperiod, expected in gas flows in molecular clouds

  16. 77 FR 6548 - Notice of Availability of Ballistic Survivability, Lethality and Vulnerability Analyses

    Science.gov (United States)

    2012-02-08

    ... DEPARTMENT OF DEFENSE Department of the Army Notice of Availability of Ballistic Survivability, Lethality and Vulnerability Analyses AGENCY: Department of the Army, DoD. ACTION: Notice of availability. SUMMARY: The US Army Research Laboratory's (ARL's), Survivability, Lethality Analysis Directorate (SLAD...

  17. Acute and sub-lethal response to mercury in Arctic and boreal calanoid copepods.

    Science.gov (United States)

    Overjordet, Ida Beathe; Altin, Dag; Berg, Torunn; Jenssen, Bjørn Munro; Gabrielsen, Geir Wing; Hansen, Bjørn Henrik

    2014-10-01

    Acute lethal toxicity, expressed as LC50 values, is a widely used parameter in risk assessment of chemicals, and has been proposed as a tool to assess differences in species sensitivities to chemicals between climatic regions. Arctic Calanus glacialis and boreal Calanus finmarchicus were exposed to mercury (Hg(2+)) under natural environmental conditions including sea temperatures of 2° and 10°C, respectively. Acute lethal toxicity (96 h LC50) and sub-lethal molecular response (GST expression; in this article gene expression is used as a synonym of gene transcription, although it is acknowledged that gene expression is also regulated, e.g., at translation and protein stability level) were studied. The acute lethal toxicity was monitored for 96 h using seven different Hg concentrations. The sub-lethal experiment was set up on the basis of nominal LC50 values for each species using concentrations equivalent to 50, 5 and 0.5% of their 96 h LC50 value. No significant differences were found in acute lethal toxicity between the two species. The sub-lethal molecular response revealed large differences both in response time and the fold induction of GST, where the Arctic species responded both faster and with higher mRNA levels of GST after 48 h exposure. Under the natural exposure conditions applied in the present study, the Arctic species C. glacialis may potentially be more susceptible to mercury exposure on the sub-lethal level. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Indirect effects of non-lethal predation on bivalve activity and sediment reworking

    NARCIS (Netherlands)

    Maire, O.; Merchant, J.N.; Bulling, M.; Teal, L.R.; Gremare, A.; Duchene, J.C.; Solan, M.

    2010-01-01

    Deposit-feeders are the dominant bioturbators of aquatic sediments, where they profoundly impact biogeochemical processes, but they are also vulnerable to both lethal and non-lethal predation by a large variety of predators. In this study, we performed a series of experiments to test the effects of

  19. Evaluating the Predictive Validity of Suicidal Intent and Medical Lethality in Youth

    Science.gov (United States)

    Sapyta, Jeffrey; Goldston, David B.; Erkanli, Alaattin; Daniel, Stephanie S.; Heilbron, Nicole; Mayfield, Andrew; Treadway, S. Lyn

    2012-01-01

    Objectives: To examine whether suicidal intent and medical lethality of past suicide attempts are predictive of future attempts, the association between intent and lethality, and the consistency of these characteristics across repeated attempts among youth. Method: Suicide attempts in a 15-year prospective study of 180 formerly psychiatrically…

  20. MHD shocks in the ISM

    Science.gov (United States)

    Chernoff, D. F.; Hollenbach, David J.; Mckee, Christopher F.

    1990-01-01

    Researchers survey shock solutions of a partially ionized gas with a magnetic field. The gas is modeled by interacting neutral, ion, electron and charged grain components. They employ a small neutral-ion chemical network to follow the dissociation and ionization of the major species. Cooling by molecular hydrogen (rotational, vibrational and dissociation), grains and dipole molecules is included. There are three basic types of solutions (C, C asterisk, and J) and some more complicated flows involving combinations of the basic types. The initial preshock conditions cover hydrogen nuclei densities of 1 less than n less than 10(exp 10) cm(-3) and shock velocities of 5 less than v(sub s) less than 60 km/s. The magnetic field is varied over 5 decades and the sensitivity of the results to grain parameters, UV and cosmic ray fluxes is ascertained. The parameter space is quite complicated, but there exist some simple divisions. When the initial ionization fraction is small (chi sub i less than 10(-5)), there is a sharp transition between fully C solutions at low velocity and strong J solutions at high velocity. When the initial ionization fraction is larger, C asterisk and/or very weak J shocks are present at low velocities in addition to the C solutions. The flow again changes to strong J shocks at high velocities. When the ionization fraction is large and the flow is only slightly greater than the bulk Alfven velocity, there is a complicated mixture of C, C asterisk and J solutions.

  1. Measuring resilience to energy shocks

    OpenAIRE

    Molyneaux, Lynette; Brown, Colin; Foster, John; Wagner, Liam

    2015-01-01

    Measuring energy security or resilience in energy is, in the main, confined to indicators which are used for comparative purposes or to show trends rather than provide empirical evidence of resilience to unpredicted crises. In this paper, the electricity systems of the individual states within the United States of America are analysed for their response to the 1973-1982 and the 2003-2012 oil price shocks. Empirical evidence is sought for elements which are present in systems that experience r...

  2. Coronal mass ejection shock fronts containing the two types of intermediate shocks

    International Nuclear Information System (INIS)

    Steinolfson, R.S.; Hundhausen, A.J.

    1990-01-01

    Numerical solutions of the time-dependent, magnetohydrodynamic (MHD) equations in two dimensions are used to demonstrate the formation of both types of intermediate shocks in a single shock front for physical conditions that are an idealization of those expected to occur in some observed coronal mass ejections. The key to producing such a shock configuration in the simulations is the use of an initial atmosphere containing a magnetic field representative of that in a coronal streamer with open field lines overlying a region of closed field lines. Previous attempts using just open field lines (perpendicular to the surface) produced shock configurations containing just one of the two intermediate shock types. A schematic of such a shock front containing both intermediate shock types has been constructed previously based solely on the known properties of MHD shocks from the Rankine-Hugoniot equations and specific requirements placed on the shock solution at points along the front where the shock normal and upstream magnetic field are aligned. The shock front also contains, at various locations along the front, a hydrodynamic (nonmagnetic) shock, a switch-on shock, and a fast shock in addition to the intermediate shocks. This particular configuration occurs when the shock front speed exceeds the upstream (preshock) intermediate wave speed but is less than a critical speed defined in the paper (equation 1) along at least some portion of the shock front. A distinctive feature of the front is that it is concave upward (away from the surface) near the region where the field in the preshock plasma is normal to the front of near the central portion of the shock front

  3. Experimental investigation of shock wave - bubble interaction

    Energy Technology Data Exchange (ETDEWEB)

    Alizadeh, Mohsen

    2010-04-09

    In this work, the dynamics of laser-generated single cavitation bubbles exposed to lithotripter shock waves has been investigated experimentally. The energy of the impinging shock wave is varied in several steps. High-speed photography and pressure field measurements simultaneously with image acquisition provide the possibility of capturing the fast bubble dynamics under the effect of the shock wave impact. The pressure measurement is performed using a fiber optic probe hydrophone (FOPH) which operates based on optical diagnostics of the shock wave propagating medium. After a short introduction in chapter 1 an overview of the previous studies in chapter 2 is presented. The reported literatures include theoretical and experimental investigations of several configurations of physical problems in the field of bubble dynamics. In chapter 3 a theoretical description of propagation of a shock wave in a liquid like water has been discussed. Different kinds of reflection of a shock wave at an interface are taken into account. Undisturbed bubble dynamics as well as interaction between a planar shock wave and an initially spherical bubble are explored theoretically. Some physical parameters which are important in this issue such as the velocity of the shock-induced liquid jet, Kelvin impulse and kinetic energy are explained. The shock waves are generated in a water filled container by a focusing piezoelectric generator. The shock wave profile has a positive part with pulse duration of ∼1 μs followed by a longer tension tail (i.e. ∼3 μs). In chapter 4 high-speed images depict the propagation of a shock wave in the water filled tank. The maximum pressure is also derived for different intensity levels of the shock wave generator. The measurement is performed in the free field (i.e. in the absence of laser-generated single bubbles). In chapter 5 the interaction between lithotripter shock waves and laserinduced single cavitation bubbles is investigated experimentally. An

  4. Effect of lethality on the extinction and on the error threshold of quasispecies.

    Science.gov (United States)

    Tejero, Hector; Marín, Arturo; Montero, Francisco

    2010-02-21

    In this paper the effect of lethality on error threshold and extinction has been studied in a population of error-prone self-replicating molecules. For given lethality and a simple fitness landscape, three dynamic regimes can be obtained: quasispecies, error catastrophe, and extinction. Using a simple model in which molecules are classified as master, lethal and non-lethal mutants, it is possible to obtain the mutation rates of the transitions between the three regimes analytically. The numerical resolution of the extended model, in which molecules are classified depending on their Hamming distance to the master sequence, confirms the results obtained in the simple model and shows how an error catastrophe regime changes when lethality is taken in account. (c) 2009 Elsevier Ltd. All rights reserved.

  5. Influence Analysis of Shell Material and Charge on Shrapnel Lethal Power

    Directory of Open Access Journals (Sweden)

    Wang Lin

    2015-01-01

    Full Text Available To compare the shrapnel lethal power with different shell material and charge, LS-DYNA was used to numerically simulate four kinds of shrapnel lethal power. The shell material was 58SiMn, 50SiMnVB or 40Cr, whereas the charge was RL-F. And the shell material was 58SiMn, whereas the charge was TNT. The shell rupture process and lethal power test were analyzed. The results show that, the lethal power of RL-F charge increase by 25%, 45%, 14% compared with the TNT charge, whereas the shell material was 58SiMn, 50SiMnVB, 40Cr. And then the guarantee range and lethal power can be improved by using the high explosive and changing shell material, whereas the projectile shape coefficient is invariable.

  6. Expressed sequence tags from heat-shocked seagrass Zostera noltii (Hornemann) from its southern distribution range.

    Science.gov (United States)

    Massa, Sónia I; Pearson, Gareth A; Aires, Tânia; Kube, Michael; Olsen, Jeanine L; Reinhardt, Richard; Serrão, Ester A; Arnaud-Haond, Sophie

    2011-09-01

    Predicted global climate change threatens the distributional ranges of species worldwide. We identified genes expressed in the intertidal seagrass Zostera noltii during recovery from a simulated low tide heat-shock exposure. Five Expressed Sequence Tag (EST) libraries were compared, corresponding to four recovery times following sub-lethal temperature stress, and a non-stressed control. We sequenced and analyzed 7009 sequence reads from 30min, 2h, 4h and 24h after the beginning of the heat-shock (AHS), and 1585 from the control library, for a total of 8594 sequence reads. Among 51 Tentative UniGenes (TUGs) exhibiting significantly different expression between libraries, 19 (37.3%) were identified as 'molecular chaperones' and were over-expressed following heat-shock, while 12 (23.5%) were 'photosynthesis TUGs' generally under-expressed in heat-shocked plants. A time course analysis of expression showed a rapid increase in expression of the molecular chaperone class, most of which were heat-shock proteins; which increased from 2 sequence reads in the control library to almost 230 in the 30min AHS library, followed by a slow decrease during further recovery. In contrast, 'photosynthesis TUGs' were under-expressed 30min AHS compared with the control library, and declined progressively with recovery time in the stress libraries, with a total of 29 sequence reads 24h AHS, compared with 125 in the control. A total of 4734 TUGs were screened for EST-Single Sequence Repeats (EST-SSRs) and 86 microsatellites were identified. Copyright © 2011 Elsevier B.V. All rights reserved.

  7. Particle Acceleration in Two Converging Shocks

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xin; Wang, Na; Shan, Hao [Xinjiang Astronomical Observatory, Chinese Academy of Sciences, Urumqi 830011 (China); Giacalone, Joe [Lunar and Planetary Laboratory, University of Arizona, Tucson AZ 85721 (United States); Yan, Yihua [CAS Key Laboratory of Solar Activity, National Astronomical Observatories, Beijing 100012 (China); Ding, Mingde, E-mail: wangxin@xao.ac.cn [Key Laboratory of Modern Astronomy and Astrophysics (Nanjing University) Ministry of Education, Nanjing 210093 (China)

    2017-06-20

    Observations by spacecraft such as ACE , STEREO , and others show that there are proton spectral “breaks” with energy E {sub br} at 1–10 MeV in some large CME-driven shocks. Generally, a single shock with the diffusive acceleration mechanism would not predict the “broken” energy spectrum. The present paper focuses on two converging shocks to identify this energy spectral feature. In this case, the converging shocks comprise one forward CME-driven shock on 2006 December 13 and another backward Earth bow shock. We simulate the detailed particle acceleration processes in the region of the converging shocks using the Monte Carlo method. As a result, we not only obtain an extended energy spectrum with an energy “tail” up to a few 10 MeV higher than that in previous single shock model, but also we find an energy spectral “break” occurring on ∼5.5 MeV. The predicted energy spectral shape is consistent with observations from multiple spacecraft. The spectral “break,” then, in this case is caused by the interaction between the CME shock and Earth’s bow shock, and otherwise would not be present if Earth were not in the path of the CME.

  8. Simulation of turbulent flows containing strong shocks

    International Nuclear Information System (INIS)

    Fryxell, Bruce; Menon, Suresh

    2008-01-01

    Simulation of turbulent flows with strong shocks is a computationally challenging problem. The requirements for a method to produce accurate results for turbulence are orthogonal to those needed to treat shocks properly. In order to prevent an unphysical rate of decay of turbulent structures, it is necessary to use a method with very low numerical dissipation. Because of this, central difference schemes are widely used. However, computing strong shocks with a central difference scheme can produce unphysical post-shock oscillations that corrupt the entire flow unless additional dissipation is added. This dissipation can be difficult to localize to the area near the shock and can lead to inaccurate treatment of the turbulence. Modern high-resolution shock-capturing methods usually use upwind algorithms to provide the dissipation necessary to stabilize shocks. However, this upwind dissipation can also lead to an unphysical rate of decay of the turbulence. This paper discusses a hybrid method for simulating turbulent flows with strong shocks that couples a high-order central difference scheme with a high-resolution shock-capturing method. The shock-capturing method is used only in the vicinity of discontinuities in the flow, whereas the central difference scheme is used in the remainder of the computational domain. Results of this new method will be shown for a variety of test problems. Preliminary results for a realistic application involving detonation in gas-particle flows will also be presented.

  9. Electron velocity distributions near collisionless shocks

    International Nuclear Information System (INIS)

    Feldman, W.C.

    1984-01-01

    Recent studies of the amount of electron heating and of the shapes of electron velocity distributions across shocks near the earth are reviewed. It is found that electron heating increases with increasing shock strength but is always less than the ion heating. The scale length of electron heating is also less than that for the ions. Electron velocity distributions show characteristic shapes which depend on the strength of the shocks. At the weaker shocks, electron heating is mostly perpendicular to the ambient magnetic field, bar B, and results in Gaussian-shaped velocity distributions at low-to-moderate energies. At the stronger shocks, parallel heating predominates resulting in flat-topped velocity distributions. A reasonable interpretation of these results indicates that at the weaker shocks electron heating is dominated by a tendency toward conservation of the magnetic moment. At the stronger fast-mode shocks, this heating is thought to be dominated by an acceleration parallel to bar B produced by the macroscopic shock electric field followed by beam driven plasma instabilities. Some contribution to the heating at the stronger shocks from conservation of the magnetic moment and cross-field current-driven instabilities cannot be ruled out. Although the heating at slow-mode shocks is also dominated by instabilities driven by magnetic field-aligned electron beams, their acceleration mechanism is not yet established

  10. Recombinant thrombomodulin protects mice against histone-induced lethal thromboembolism.

    Directory of Open Access Journals (Sweden)

    Mayumi Nakahara

    Full Text Available INTRODUCTION: Recent studies have shown that histones, the chief protein component of chromatin, are released into the extracellular space during sepsis, trauma, and ischemia-reperfusion injury, and act as major mediators of the death of an organism. This study was designed to elucidate the cellular and molecular basis of histone-induced lethality and to assess the protective effects of recombinant thrombomodulin (rTM. rTM has been approved for the treatment of disseminated intravascular coagulation (DIC in Japan, and is currently undergoing a phase III clinical trial in the United States. METHODS: Histone H3 levels in plasma of healthy volunteers and patients with sepsis and DIC were measured using enzyme-linked immunosorbent assay. Male C57BL/6 mice were injected intravenously with purified histones, and pathological examinations were performed. The protective effects of rTM against histone toxicity were analyzed both in vitro and in mice. RESULTS: Histone H3 was not detectable in plasma of healthy volunteers, but significant levels were observed in patients with sepsis and DIC. These levels were higher in non-survivors than in survivors. Extracellular histones triggered platelet aggregation, leading to thrombotic occlusion of pulmonary capillaries and subsequent right-sided heart failure in mice. These mice displayed symptoms of DIC, including thrombocytopenia, prolonged prothrombin time, decreased fibrinogen, fibrin deposition in capillaries, and bleeding. Platelet depletion protected mice from histone-induced death in the first 30 minutes, suggesting that vessel occlusion by platelet-rich thrombi might be responsible for death during the early phase. Furthermore, rTM bound to extracellular histones, suppressed histone-induced platelet aggregation, thrombotic occlusion of pulmonary capillaries, and dilatation of the right ventricle, and rescued mice from lethal thromboembolism. CONCLUSIONS: Extracellular histones cause massive

  11. A novel homozygous variant in SERPINH1 associated with a severe, lethal presentation of osteogenesis imperfecta with hydranencephaly.

    Science.gov (United States)

    Marshall, Charlotte; Lopez, Jaime; Crookes, Laura; Pollitt, Rebecca C; Balasubramanian, Meena

    2016-12-20

    Osteogenesis imperfecta (OI) is a genetic disorder characterised by low bone mineral density resulting in fractures. 85-90% of patients with OI carry a variant in the type 1 collagen genes, COL1A1 and COL1A2, which follows an autosomal dominant pattern of inheritance. However, within the last two decades, there have been growing number of variants identified in genes that follow an autosomal recessive pattern of inheritance. Our proband is a child born in Mexico with multiple fractures of ribs, minimal calvarial mineralisation, platyspondyly, marked compression and deformed long bones. He also presented with significant hydranencephaly, requiring ventilatory support from birth, and died at 8days of age. A homozygous c.338_357delins22 variant in exon 2 of SERPINH1 was identified. This gene encodes heat shock protein 47, a collagen-specific chaperone which binds to the procollagen triple helix and is responsible for collagen stabilisation in the endoplasmic reticulum. There is minimal literature on the mechanism of action for variants in SERPINH1 resulting in osteogenesis imperfecta. Here we discuss this rare, previously unreported variant, and expand on the phenotypic presentation of this novel variant resulting in a severe, lethal phenotype of OI in association with hydranencephaly. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Passive therapy with humanized anti-staphylococcal enterotoxin B antibodies attenuates systemic inflammatory response and protects from lethal pneumonia caused by staphylococcal enterotoxin B-producing Staphylococcus aureus.

    Science.gov (United States)

    Karau, Melissa J; Tilahun, Mulualem E; Krogman, Ashton; Osborne, Barbara A; Goldsby, Richard A; David, Chella S; Mandrekar, Jayawant N; Patel, Robin; Rajagopalan, Govindarajan

    2017-10-03

    Drugs such as linezolid that inhibit bacterial protein synthesis may be beneficial in treating infections caused by toxigenic Staphylococcus aureus. As protein synthesis inhibitors have no effect on preformed toxins, neutralization of pathogenic exotoxins with anti-toxin antibodies may be beneficial in conjunction with antibacterial therapy. Herein, we evaluated the efficacy of human-mouse chimeric high-affinity neutralizing anti-staphylococcal enterotoxin B (SEB) antibodies in the treatment of experimental pneumonia caused by SEB-producing S. aureus. Since HLA class II transgenic mice mount a stronger systemic immune response following challenge with SEB and are more susceptible to SEB-induced lethal toxic shock than conventional mice strains, HLA-DR3 transgenic mice were used. Lethal pneumonia caused by SEB-producing S. aureus in HLA-DR3 transgenic mice was characterized by robust T cell activation and elevated systemic levels of several pro-inflammatory cytokines and chemokines. Prophylactic administration of a single dose of linezolid 30 min prior to the onset of infection attenuated the systemic inflammatory response and protected from mortality whereas linezolid administered 60 min after the onset of infection failed to confer significant protection. Human-mouse chimeric high-affinity neutralizing anti-SEB antibodies alone, but not polyclonal human IgG, mitigated this response and protected from death when administered immediately after initiation of infection. Further, anti-SEB antibodies as well as intact polyclonal human IgG, but not its Fab or Fc fragments, protected from lethal pneumonia when followed with linezolid therapy 60 min later. In conclusion, neutralization of superantigens with high-affinity antibodies may have beneficial effects in pneumonia.

  13. Therapeutic efficacy of antibodies lacking Fcγ receptor binding against lethal dengue virus infection is due to neutralizing potency and blocking of enhancing antibodies [corrected].

    Directory of Open Access Journals (Sweden)

    Katherine L Williams

    2013-02-01

    Full Text Available Dengue hemorrhagic fever and dengue shock syndrome (DHF/DSS are life-threatening complications following infection with one of the four serotypes of dengue virus (DENV. At present, no vaccine or antiviral therapies are available against dengue. Here, we characterized a panel of eight human or mouse-human chimeric monoclonal antibodies (MAbs and their modified variants lacking effector function and dissected the mechanism by which some protect against antibody-enhanced lethal DENV infection. We found that neutralizing modified MAbs that recognize the fusion loop or the A strand epitopes on domains II and III of the envelope protein, respectively, act therapeutically by competing with and/or displacing enhancing antibodies. By analyzing these relationships, we developed a novel in vitro suppression-of-enhancement assay that predicts the ability of modified MAbs to act therapeutically against antibody-enhanced disease in vivo. These studies provide new insight into the biology of DENV pathogenesis and the requirements for antibodies to treat lethal DENV disease.

  14. 35S induced dominant lethals in immature Oocytes in mice

    International Nuclear Information System (INIS)

    Satyanarayana Reddy, K.; Reddy, P.; Reddy, O.S.

    1976-01-01

    CBA female mice were injected intraperitoneally with a dose of 20 μCi of sulphur-35 on 15.5 day post conception. Another group of pregnant mice injected with normal saline was kept as control. The pregnant females were allowed to litter and the mothers were separated from their offspring 4 weeks after littering. Eight weeks after treatment i.e. at the age of 22-24 weeks, the treated mothers were mated to control C 3 H/He males. The vaginal plugs were checked everyday morning and those mated were separated. The pregnants were killed on 14th day of gestation. The uterine contents were searched for live and dead embryos and the ovaries for corpora lutea. The pre, post and total loses were calculated in the treated females and compared with those of control. The statistical tests performed indicated that all losses are significant. The results indicate that 35 S can induce chromosomal breaks in immature oocytes and lead to the induction of dominant lethals. (author)

  15. Successful Treatment of Acute Lethal Dose of Acrylamide Poisoning

    Directory of Open Access Journals (Sweden)

    Ali Banagozar Mohammadi

    2015-03-01

    Full Text Available Background: Acrylamide (C3H5NO is a vinyl monomer. This water-soluble crystalline solid is a colorless, odorless agent which is used in scientific laboratories and some industries. Acrylamide has cellular oxidative effects. Acute or chronic poisoning with this agent happens as a result of skin, respiratory, or oral contacts. Clinical manifestations depend on the dose, duration, and frequency of contact. Management of these patients consists of conservative and palliative therapies to reduce the oxidative effects. Case: The case was a 29-year-old girl with a Master of Sciences degree in genetics who worked in a university research center with previous history of depression. She had ingested 100cc of 30% Acrylamide solution for intentional suicide attempt. The patient was successfully managed using N-acetyl cysteine, vitamin C, and melatonin. Conclusion: Early diagnosis and appropriate treatment with recommended agents together with supportive therapies can save the life of patients exposed to potentially lethal doses of acrylamide, although intentional or accidental.

  16. Lethal effect of glucose load on malignant cells

    International Nuclear Information System (INIS)

    Shmakova, N.L.; Yarmonenko, S.P.; Kozubek, S.

    1987-01-01

    Ehrlich ascites tumor (EAT) cells were treated with glucose load under anoxic conditions (for 15 or 60 min) and/or with γ radiation (20 Gy). The efficiency of the treatment was judged from the tumorigenic activity of EAT cell inocula. The markedly increased efficiency of the combined treatment of EAT cells using glucose load in anoxia and γ radiation is due to the additive action of both agents. The glucose load in anoxia leads to extensive desintegration of tumor cells. Further, the lethal effect of various pH values on EAT cells was investigated. Different pH values were obtained by means of both glucose load and phosphate buffers. The effect was investigated by determining the tumorigenic activity of EAT cells tested in vivo in mice and by determining the radiosensitivity of treated EAT cells. The results allowed us to conclude that the same values of pH lead to the same effect on EAT cells independently of the way by which the given pH value was reached. (author). 5 figs., 2 tabs., 12 refs

  17. Lethal Lullabies: A History of Opium Use in Infants.

    Science.gov (United States)

    Obladen, Michael

    2016-02-01

    Poppy extract accompanied the human infant for more than 3 millenia. Motives for its use included excessive crying, suspected pain, and diarrhea. In antiquity, infantile sleeplessness was regarded as a disease. When treatment with opium was recommended by Galen, Rhazes, and Avicenna, baby sedation made its way into early medical treatises and pediatric instructions. Dabbing maternal nipples with bitter substances and drugging the infant with opium were used to hasten weaning. A freerider of gum lancing, opiates joined the treatment of difficult teething in the 17th century. Foundling hospitals and wet-nurses used them extensively. With industrialization, private use was rampant among the working class. In German-speaking countries, poppy extracts were administered in soups and pacifiers. In English-speaking countries, proprietary drugs containing opium were marketed under names such as soothers, nostrums, anodynes, cordials, preservatives, and specifics and sold at the doorstep or in grocery stores. Opium's toxicity for infants was common knowledge; thousands of cases of lethal intoxication had been reported from antiquity. What is remarkable is that the willingness to use it in infants persisted and that physicians continued to prescribe it for babies. Unregulated trade, and even that protected by governments, led to greatly increased private use of opiates during the 19th century. Intoxication became a significant factor in infant mortality. As late as 1912, the International Hague Convention forced governments to implement legislation that effectively curtailed access to opium and broke the dangerous habit of sedating infants. © The Author(s) 2015.

  18. Internet suicide: communities of affirmation and the lethality of communication.

    Science.gov (United States)

    Niezen, Ronald

    2013-04-01

    As a tool of instant information dissemination and social networking, the Internet has made possible the formation and affirmation of public identities based on personality traits that are usually characterized by clinicians as pathological. The wide variety of online communities of affirmation reveals new conditions for permissiveness and inclusiveness in expressions of these socially marginal and clinically pathologized identities. Much the same kind of discourse common to these online communities is evident in some suicide forums. Web sites with suicide as their central raison d'être, taken together, encompass a wide range of ideas and commitments, including many that provide collective affirmation outside of (and often with hostility toward) professional intervention. The paradox of a potentially life-affirming effect of such forums runs counter to a stark dualism between online therapy versus "prochoice" forums and, by extension, to simple models of the influence of ideas on the lethality of suicide. Different forums either intensify or mitigate self-destructive tendencies in ways that are significant for understanding the place of communication in the occurrence of suicide and for therapeutic practice.

  19. Computer simulations of collisionless shock waves

    International Nuclear Information System (INIS)

    Leroy, M.M.

    1984-01-01

    A review of the contributions of particle computer simulations to the understanding of the physics of magnetic shock waves in collisionless plasmas is presented. The emphasis is on the relation between the computer simulation results, spacecraft observations of shocks in space, and related theories, rather than on technical aspects of the numerics. It is shown that much has been learned from the comparison of ISEE spacecraft observations of the terrestrial bow shock and particle computer simulations concerning the quasi-perpendicular, supercritical shock (ion scale structure, ion reflection mechanism and ultimate dissipation processes). Particle computer simulations have also had an appreciable prospective role in the investigation of the physics of quasi-parallel shocks, about which still little is known observationally. Moreover, these numerical techniques have helped to clarify the process of suprathermal ion rejection by the shock into the foreshock, and the subsequent evolution of the ions in the foreshock. 95 references

  20. Molecular dynamics simulation of laser shock phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Fukumoto, Ichirou [Japan Atomic Energy Research Inst., Kansai Research Establishment, Advanced Photon Research Center, Neyagawa, Osaka (Japan).

    2001-10-01

    Recently, ultrashort-pulse lasers with high peak power have been developed, and their application to materials processing is expected as a tool of precision microfabrication. When a high power laser irradiates, a shock wave propagates into the material and dislocations are generated. In this paper, laser shock phenomena of the metal were analyzed using the modified molecular dynamics method, which has been developed by Ohmura and Fukumoto. The main results obtained are summarized as follows: (1) The shock wave induced by the Gaussian beam irradiation propagates radially from the surface to the interior. (2) A lot of dislocations are generated at the solid-liquid interface by the propagation of a shock wave. (3) Some dislocations are moved instantaneously with the velocity of the longitudinal wave when the shock wave passes, and their velocity is not larger than the transverse velocity after the shock wave has passed. (author)

  1. Entropy Generation Across Earth's Bow Shock

    Science.gov (United States)

    Parks, George K.; McCarthy, Michael; Fu, Suiyan; Lee E. s; Cao, Jinbin; Goldstein, Melvyn L.; Canu, Patrick; Dandouras, Iannis S.; Reme, Henri; Fazakerley, Andrew; hide

    2011-01-01

    Earth's bow shock is a transition layer that causes an irreversible change in the state of plasma that is stationary in time. Theories predict entropy increases across the bow shock but entropy has never been directly measured. Cluster and Double Star plasma experiments measure 3D plasma distributions upstream and downstream of the bow shock that allow calculation of Boltzmann's entropy function H and his famous H-theorem, dH/dt O. We present the first direct measurements of entropy density changes across Earth's bow shock. We will show that this entropy generation may be part of the processes that produce the non-thermal plasma distributions is consistent with a kinetic entropy flux model derived from the collisionless Boltzmann equation, giving strong support that solar wind's total entropy across the bow shock remains unchanged. As far as we know, our results are not explained by any existing shock models and should be of interests to theorists.

  2. Remote shock sensing and notification system

    Science.gov (United States)

    Muralidharan, Govindarajan; Britton, Charles L.; Pearce, James; Jagadish, Usha; Sikka, Vinod K.

    2008-11-11

    A low-power shock sensing system includes at least one shock sensor physically coupled to a chemical storage tank to be monitored for impacts, and an RF transmitter which is in a low-power idle state in the absence of a triggering signal. The system includes interference circuitry including or activated by the shock sensor, wherein an output of the interface circuitry is coupled to an input of the RF transmitter. The interface circuitry triggers the RF transmitting with the triggering signal to transmit an alarm message to at least one remote location when the sensor senses a shock greater than a predetermined threshold. In one embodiment the shock sensor is a shock switch which provides an open and a closed state, the open state being a low power idle state.

  3. Refeeding syndrome: a forgotten and potentially lethal entity.

    Science.gov (United States)

    Aissaoui, Y; Hammi, S; Tagajdid, R; Chkoura, K; Boughalem, M

    2016-05-01

    Refeeding syndrome (RS) is defined as the fluid, electrolyte, metabolic, and clinical disturbances that occur after nutrition of patients who have been undernourished or fasting for a prolonged period. This syndrome has been recognized for several decades but is most often overlooked and underdiagnosed by health professionals. The authors report a RS in a patient subjected to prolonged fasting after being kidnapped by a criminal gang. Refeeding resulted in severe hypophosphatemia, neurological impairments, and hematologic disorders. The patient died due to septic shock with multiple organ failure secondary to aspiration pneumonia. In this case, the failure to recognize RS was decisive in the fatal outcome. Professionals must be aware of this disease to prevent and treat it properly.

  4. Role of echocardiography in reducing shock reversal time in pediatric septic shock: a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Ahmed A. EL‐Nawawy

    2018-01-01

    Conclusion: Serial echocardiography provided crucial data for early recognition of septic myocardial dysfunction and hypovolemia that was not apparent on clinical assessment, allowing a timely management and resulting in shock reversal time reduction among children with septic shock.

  5. The earth's foreshock, bow shock, and magnetosheath

    Science.gov (United States)

    Onsager, T. G.; Thomsen, M. F.

    1991-01-01

    Studies directly pertaining to the earth's foreshock, bow shock, and magnetosheath are reviewed, and some comparisons are made with data on other planets. Topics considered in detail include the electron foreshock, the ion foreshock, the quasi-parallel shock, the quasi-perpendicular shock, and the magnetosheath. Information discussed spans a broad range of disciplines, from large-scale macroscopic plasma phenomena to small-scale microphysical interactions.

  6. The earth's foreshock, bow shock, and magnetosheath

    International Nuclear Information System (INIS)

    Onsager, T.G.; Thomsen, M.F.

    1991-01-01

    Studies directly pertaining to the earth's foreshock, bow shock, and magnetosheath are reviewed, and some comparisons are made with data on other planets. Topics considered in detail include the electron foreshock, the ion foreshock, the quasi-parallel shock, the quasi-perpendicular shock, and the magnetosheath. Information discussed spans a broad range of disciplines, from large-scale macroscopic plasma phenomena to small-scale microphysical interactions. 184 refs

  7. Nonequilibrium chemistry in shocked molecular clouds

    International Nuclear Information System (INIS)

    Iglesias, E.R.; Silk, J.

    1978-01-01

    The gas phase chemistry is studied behind a 10 km s -1 shock propagating into a dense molecular cloud. Our principal conclusions are that the concentrations of certain molecules (CO, NH 3 , HCN, N 2 ) are unperturbed by the shock; other molecules (H 2 CO, CN, HCO + ) are greatly decreased in abundance; and substantial amounts of H 2 O, HCO, and CH 4 are produced. Approximately 10 6 yr (independent of the density) must elapse after shock passage before chemical equilibrium is attained

  8. Reaction effects in diffusive shock acceleration

    International Nuclear Information System (INIS)

    Drury, L.Oc.

    1984-01-01

    The effects of the reaction of accelerated particles back on the shock wave in the diffusive-shock-acceleration model of cosmic-ray generation are investigated theoretically. Effects examined include changes in the shock structure, modifications of the input and output spectra, scattering effects, and possible instabilities in the small-scale structure. It is pointed out that the latter two effects are applicable to any spatially localized acceleration mechanism. 14 references

  9. PIV tracer behavior on propagating shock fronts

    International Nuclear Information System (INIS)

    Glazyrin, Fyodor N; Mursenkova, Irina V; Znamenskaya, Irina A

    2016-01-01

    The present work was aimed at the quantitative particle image velocimetry (PIV) measurement of a velocity field near the front of a propagating shock wave and the study of the dynamics of liquid tracers crossing the shock front. For this goal, a shock tube with a rectangular cross-section (48  ×  24 mm) was used. The flat shock wave with Mach numbers M  =  1.4–2.0 propagating inside the tube channel was studied as well as an expanding shock wave propagating outside the channel with M  =  1.2–1.8 at its main axis. The PIV imaging of the shock fronts was carried out with an aerosol of dioctyl sebacate (DEHS) as tracer particles. The pressures of the gas in front of the shock waves studied ranged from 0.013 Mpa to 0.1 MPa in the series of experiments. The processed PIV data, compared to the 1D normal shock theory, yielded consistent values of wake velocity immediately behind the plain shock wave. Special attention was paid to the blurring of the velocity jump on the shock front due to the inertial particle lag and peculiarities of the PIV technique. A numerical algorithm was developed for analysis and correction of the PIV data on the shock fronts, based on equations of particle-flow interaction. By application of this algorithm, the effective particle diameter of the DEHS aerosol tracers was estimated as 1.03  ±  0.12 μm. A number of different formulations for particle drag were tested with this algorithm, with varying success. The results show consistency with previously reported experimental data obtained for cases of stationary shock waves. (paper)

  10. Lethality of Rendang packaged in multilayer retortable pouch with sterilization process

    Science.gov (United States)

    Praharasti, A. S.; Kusumaningrum, A.; Frediansyah, A.; Nurhikmat, A.; Khasanah, Y.; Suprapedi

    2017-01-01

    Retort Pouch had become a choice to preserve foods nowadays, besides the used of the can. Both had their own advantages, and Retort Pouch became more popular for the reason of cheaper and easier to recycle. General Method usually used to estimate the lethality of commercial heat sterilization process. Lethality value wa s used for evaluating the efficacy of the thermal process. This study aimed to find whether different layers of pouch materials affect the lethality value and to find differences lethality in two types of multilayer retort pouch, PET/Aluminum Foil/Nylon/RCPP and PET/Nylon/Modified Aluminum/CPP. The result showed that the different layer arrangement was resulted different Sterilization Value (SV). PET/Nylon/Modified Aluminum/CPP had better heat penetration, implied by the higher value of lethality. PET/Nylon/Modified Aluminum/CPP had the lethality value of 6,24 minutes, whereas the lethality value of PET/Aluminum Foil/Nylon/RCPP was 3,54 minutes.

  11. A bacterial cocaine esterase protects against cocaine-induced epileptogenic activity and lethality.

    Science.gov (United States)

    Jutkiewicz, Emily M; Baladi, Michelle G; Cooper, Ziva D; Narasimhan, Diwahar; Sunahara, Roger K; Woods, James H

    2009-09-01

    Cocaine toxicity results in cardiovascular complications, seizures, and death and accounts for approximately 20% of drug-related emergency department visits every year. Presently, there are no treatments to eliminate the toxic effects of cocaine. The present study hypothesizes that a bacterial cocaine esterase with high catalytic efficiency would provide rapid and robust protection from cocaine-induced convulsions, epileptogenic activity, and lethality. Cocaine-induced paroxysmal activity and convulsions were evaluated in rats surgically implanted with radiotelemetry devices (N=6 per treatment group). Cocaine esterase was administered 1 minute after a lethal dose of cocaine or after cocaine-induced convulsions to determine the ability of the enzyme to prevent or reverse, respectively, the effects of cocaine. The cocaine esterase prevented all cocaine-induced electroencephalographic changes and lethality. This effect was specific for cocaine because the esterase did not prevent convulsions and death induced by a cocaine analog, (-)-2beta-carbomethoxy-3beta-phenyltropane. The esterase prevented lethality even after cocaine-induced convulsions occurred. In contrast, the short-acting benzodiazepine, midazolam, prevented cocaine-induced convulsions but not the lethal effects of cocaine. The data showed that cocaine esterase successfully degraded circulating cocaine to prevent lethality and that cocaine-induced convulsions alone are not responsible for the lethal effects of cocaine in this model. Therefore, further investigation into the use of cocaine esterase for treating cocaine overdose and its toxic effects is warranted.

  12. Condensed matter at high shock pressures

    International Nuclear Information System (INIS)

    Nellis, W.J.; Holmes, N.C.; Mitchell, A.C.; Radousky, H.B.; Hamilton, D.

    1985-01-01

    Experimental techniques are described for shock waves in liquids: Hugoniot equation-of-state, shock temperature and emission spectroscopy, electrical conductivity, and Raman spectroscopy. Experimental data are reviewed and presented in terms of phenomena that occur at high densities and temperatures in shocked He, Ar, N 2 , CO, SiO 2 -aerogel, H 2 O, and C 6 H 6 . The superconducting properties of Nb metal shocked to 100 GPa (1 Mbar) and recovered intact are discussed in terms of prospects for synthesizing novel, metastable materials. Ultrahigh pressure data for Cu is reviewed in the range 0.3 to 6TPa (3 to 60 Mbar). 56 refs., 9 figs., 1 tab

  13. Radio emission from coronal and interplanetary shocks

    International Nuclear Information System (INIS)

    Cane, H.V.

    1987-01-01

    Observational data on coronal and interplanetary (IP) type II burst events associated with shock-wave propagation are reviewed, with a focus on the past and potential future contributions of space-based observatories. The evidence presented by Cane (1983 and 1984) in support of the hypothesis that the coronal (metric) and IP (kilometric) bursts are due to different shocks is summarized, and the fast-drift kilometric events seen at the same time as metric type II bursts (and designated shock-accelerated or shock-associated events) are characterized. The need for further observations at 0.5-20 MHz is indicated. 20 references

  14. Advanced and Exploratory Shock Sensing Mechanisms.

    Energy Technology Data Exchange (ETDEWEB)

    Nelsen, Nicholas H. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Kolb, James D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Kulkarni, Akshay G. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Sorscher, Zachary [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Habing, Clayton D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Mathis, Allen [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Beller, Zachary J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-09-01

    Mechanical component response to shock environments must be predictable in order to ensure reliability and safety. Whether the shock input results from accidental drops during transportation to projectile impact scenarios, the system must irreversibly transition into a safe state that is incapable of triggering the component . With this critical need in mind, the 2017 Nuclear Weapons Summer Product Realization Institute (NW SPRINT) program objective sought the design of a passive shock failsafe with emphasis on additively manufactured (AM) components. Team Advanced and Exploratory (A&E) responded to the challenge by designing and delivering multiple passive shock sensing mech anisms that activate within a prescribed mechanical shock threshold. These AM failsafe designs were tuned and validated using analytical and computational techniques including the shock response spectrum (SRS) and finite element analysis (FEA). After rapid prototyping, the devices experienced physical shock tests conducted on Sandia drop tables to experimentally verify performance. Keywords: Additive manufacturing, dynamic system, failsafe, finite element analysis, mechanical shock, NW SPRINT, shock respon se spectrum

  15. Irreversible thermodynamics of overdriven shocks in solids

    International Nuclear Information System (INIS)

    Wallace, D.C.

    1981-01-01

    An isotropic solid capable of transporting heat and of undergoing dissipative plastic flow, is treated. The shock is assumed to be a steady wave, and any phase changes or macroscopic inhomogeneities which might be induced by the shock are neglected. Under these conditions it is established that for an overdriven shock, no solution is possible without heat transport, and when the heat transport is governed by the steady conduction equation, no solution is possible without plastic dissipation as well. Upper and lower bounds are established for the thermodynamic variables, namely the shear stress, temperature, entropy, plastic strain, and heat flux, as functions of compression through the shock

  16. The source of real and nominal exchange rate fluctuations in Thailand: Real shock or nominal shock

    OpenAIRE

    Le Thanh, Binh

    2015-01-01

    This paper examines the source of exchange rate fluctuations in Thailand. We employed a structural vector auto-regression (SVAR) model with the long-run neutrality restriction of Blanchard and Quah (1989) to investigate the changes in real and nominal exchange rates from 1994 to 2015. In this paper, we assume that there are two types of shocks which related to exchange rate movements: real shocks and nominal shocks. The empirical analysis indicates that real shocks are the fundamental compon...

  17. Relative Risks for Lethal Prostate Cancer Based on Complete Family History of Prostate Cancer Death.

    Science.gov (United States)

    Albright, Frederick S; Stephenson, Robert A; Agarwal, Neeraj; Cannon-Albright, Lisa A

    2017-01-01

    There are few published familial relative risks (RR) for lethal prostate cancer. This study estimates RRs for lethal prostate cancer based on comprehensive family history data, with the goal of improving identification of those men at highest risk of dying from prostate cancer. We used a population-based genealogical resource linked to a statewide electronic SEER cancer registry and death certificates to estimate relative risks (RR) for death from prostate cancer based upon family history. Over 600,000 male probands were analyzed, representing a variety of family history constellations of lethal prostate cancer. RR estimates were based on the ratio of the observed to the expected number of lethal prostate cancer cases using internal rates. RRs for lethal prostate cancer based on the number of affected first-degree relatives (FDR) ranged from 2.49 (95% CI: 2.27, 2.73) for exactly 1 FDR to 5.30 (2.13, 10.93) for ≥3 affected FDRs. In an absence of affected FDRs, increased risk was also significant for increasing numbers of affected second-degree or third degree relatives. Equivalent risks were observed for similar maternal and paternal family history. This study provides population-based estimates of lethal prostate cancer risk based on lethal prostate cancer family history. Many family history constellations associated with two to greater than five times increased risk for lethal prostate cancer were identified. These lethal prostate cancer risk estimates hold potential for use in identification, screening, early diagnosis, and treatment of men at high risk for death from prostate cancer. Prostate77:41-48, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  18. Model for shock wave chaos.

    Science.gov (United States)

    Kasimov, Aslan R; Faria, Luiz M; Rosales, Rodolfo R

    2013-03-08

    We propose the following model equation, u(t) + 1/2(u(2)-uu(s))x = f(x,u(s)) that predicts chaotic shock waves, similar to those in detonations in chemically reacting mixtures. The equation is given on the half line, xorder partial differential equation. The chaos arises in the equation thanks to an interplay between the nonlinearity of the inviscid Burgers equation and a novel forcing term that is nonlocal in nature and has deep physical roots in reactive Euler equations.

  19. Adaptive inertial shock-absorber

    International Nuclear Information System (INIS)

    Faraj, Rami; Holnicki-Szulc, Jan; Knap, Lech; Seńko, Jarosław

    2016-01-01

    This paper introduces and discusses a new concept of impact absorption by means of impact energy management and storage in dedicated rotating inertial discs. The effectiveness of the concept is demonstrated in a selected case-study involving spinning management, a recently developed novel impact-absorber. A specific control technique performed on this device is demonstrated to be the main source of significant improvement in the overall efficiency of impact damping process. The influence of various parameters on the performance of the shock-absorber is investigated. Design and manufacturing challenges and directions of further research are formulated. (paper)

  20. Photoreactivable sector of lethal damage in ultraviolet-irradiated Escherichia coli cells

    International Nuclear Information System (INIS)

    Balgavy, P.

    1976-01-01

    The photoreactivable sector of lethal damage in Escherichia coli Bsub(s-1), Escherichia coli B/r Hcr - and Escherichia coli B/r Hcr + cells after ultraviolet irradiation at 254 nm is 0.823 +- 0.004, 0.70 +- 0.01 and 0.53 +- 0.06, respectively, at 99% confidence limits. For the low values of the photoreactivable sector in the B/r Hcr - and B/r Hcr + strains are likely to be responsible dark repair processes which eliminate lethal damage, brought about by pyrimidine dimers, preferably in comparison with lethal damage caused by photoproducts of another type. (author)

  1. A reliable method for reconstituting thymectomized, lethally irradiated guinea pigs with bone marrow cells

    International Nuclear Information System (INIS)

    Terata, N.; Tanio, Y.; Zbar, B.

    1984-01-01

    The authors developed a reliable method for reconstituting thymectomized, lethally irradiated guinea pigs. Injection of 2.5-10 x 10 7 syngeneic bone marrow cells into adult thymectomized, lethally irradiated guinea pigs produced survival of 46-100% of treated animals. Gentamycin sulfate (5 mg/kg of body weight) for 10 days was required for optimal results. Acidified drinking water (pH 2.5) appeared to be required for optimal results. Thymectomized, lethally irradiated, bone marrow reconstituted ('B') guinea pigs had impaired ability to develop delayed cutaneous hypersensitivity to mycobacterial antigens and cutaneous basophil hypersensitivity to keyhole limpet hemocyanin; proliferative responses to phytohemagglutinin were impaired. (Auth.)

  2. Recombinant raccoon pox vaccine protects mice against lethal plague

    Science.gov (United States)

    Osorio, J.E.; Powell, T.D.; Frank, R.S.; Moss, K.; Haanes, E.J.; Smith, S.R.; Rocke, T.E.; Stinchcomb, D.T.

    2003-01-01

    Using a raccoon poxvirus (RCN) expression system, we have developed new recombinant vaccines that can protect mice against lethal plague infection. We tested the effects of a translation enhancer (EMCV-IRES) in combination with a secretory (tPA) signal or secretory (tPA) and membrane anchoring (CHV-gG) signals on in vitro antigen expression of F1 antigen in tissue culture and the induction of antibody responses and protection against Yersinia pestis challenge in mice. The RCN vector successfully expressed the F1 protein of Y. pestis in vitro. In addition, the level of expression was increased by the insertion of the EMCV-IRES and combinations of this and the secretory signal or secretory and anchoring signals. These recombinant viruses generated protective immune responses that resulted in survival of 80% of vaccinated mice upon challenge with Y. pestis. Of the RCN-based vaccines we tested, the RCN-IRES-tPA-YpF1 recombinant construct was the most efficacious. Mice vaccinated with this construct withstood challenge with as many as 1.5 million colony forming units of Y. pestis (7.7×104 LD50). Interestingly, vaccination with F1 fused to the anchoring signal (RCN-IRES-tPA-YpF1-gG) elicited significant anti-F1 antibody titers, but failed to protect mice from plague challenge. Our studies demonstrate, in vitro and in vivo, the potential importance of the EMCV-IRES and secretory signals in vaccine design. These molecular tools provide a new approach for improving the efficacy of vaccines. In addition, these novel recombinant vaccines could have human, veterinary, and wildlife applications in the prevention of plague.

  3. Analyzing temporal variation in the lethality of ETA

    Directory of Open Access Journals (Sweden)

    Sánchez-Cuenca, Ignacio

    2009-12-01

    Full Text Available This article analyzes time variation in the lethal violence of the terrorist organization ETA. Given the dynamic structure of the time series of fatalities, I look at the effect of a number of independent variables (the celebration of different types of elections, anti-ETA activity by extreme right-wing organizations and the GAL, police arrests, and other relevant events, such as the referendums on the Constitution and the Statute of Autonomy of Guernica. To do so, I have estimated several ARIMA models using the time series of fatalities between 1968 and 2007. Moreover, the results obtained are complemented by a historical-political analysis of the period of maximum violence, which took place during the Spanish transition to democracy.

    Este artículo analiza la variación temporal en la violencia letal de la organización terrorista ETA. Dada la estructura dinámica de la serie temporal de víctimas mortales, se estudia el efecto de una serie de variables independientes (celebración de distintos tipos de elecciones, actividad anti-ETA de la extrema derecha y del GAL, detenciones policiales y sucesos especiales como los referendos sobre la Constitución o el Estatuto de Autonomía de Guernica. Para ello, se estiman diversos modelos ARIMA con la serie trimestral de víctimas mortales entre 1968 y 2007. Además, se completan los resultados obtenidos con un análisis histórico-político del periodo de máxima violencia durante la transición a la democracia.

  4. Lethal action of soluble metallic salts on fishes

    Energy Technology Data Exchange (ETDEWEB)

    Carpenter, K E

    1927-01-01

    A study of pollution of Welsh rivers by lead-mine effluents revealed the fact that fishes were killed by the action of soluble salts of lead, which proved lethal at concentrations so low as pb i : 3,000,000. A physiological investigation of the action of lead-salts revealed the following facts: the action does not correspond to the normal toxic type. The graph of survival-times in different concentrations closely follows the equation: K = i/t log i/conc. The speed of the reaction is dependent upon the total quantity of metallic ion present, as well as upon the actual concentrations. The speed of the reaction varies in inverse relation to the size and weight of fishes employed. The most marked symptom is the formation of a film over gills and skin, by interaction of the metallic ion with a mucus-constituent. Death by suffocation is the final result. Where insufficient lead ion is present, the film is shed off, and complete recovery takes place. The speed of the reaction varies in direct relation to the temperature. Chemical analysis of residues shows that no trace of metallic ion penetrates into the body itself. The action is thus held to be purely external in process, chemical in type, and mechanical in effect; i.e., it is not a toxic action in the ordinary sense of the term. The action of soluble salts of zinc, iron, copper, cadmium, and mercury is shown to follow the same law as that of lead. Attention is directed to the economic importance of the facts, in connection with the pollution of rivers.

  5. MKLN1 splicing defect in dogs with lethal acrodermatitis.

    Directory of Open Access Journals (Sweden)

    Anina Bauer

    2018-03-01

    Full Text Available Lethal acrodermatitis (LAD is a genodermatosis with monogenic autosomal recessive inheritance in Bull Terriers and Miniature Bull Terriers. The LAD phenotype is characterized by poor growth, immune deficiency, and skin lesions, especially at the paws. Utilizing a combination of genome wide association study and haplotype analysis, we mapped the LAD locus to a critical interval of ~1.11 Mb on chromosome 14. Whole genome sequencing of an LAD affected dog revealed a splice region variant in the MKLN1 gene that was not present in 191 control genomes (chr14:5,731,405T>G or MKLN1:c.400+3A>C. This variant showed perfect association in a larger combined Bull Terrier/Miniature Bull Terrier cohort of 46 cases and 294 controls. The variant was absent from 462 genetically diverse control dogs of 62 other dog breeds. RT-PCR analysis of skin RNA from an affected and a control dog demonstrated skipping of exon 4 in the MKLN1 transcripts of the LAD affected dog, which leads to a shift in the MKLN1 reading frame. MKLN1 encodes the widely expressed intracellular protein muskelin 1, for which diverse functions in cell adhesion, morphology, spreading, and intracellular transport processes are discussed. While the pathogenesis of LAD remains unclear, our data facilitate genetic testing of Bull Terriers and Miniature Bull Terriers to prevent the unintentional production of LAD affected dogs. This study may provide a starting point to further clarify the elusive physiological role of muskelin 1 in vivo.

  6. Can Telescopes Help Leo Satellites Dodge Most Lethal Impacts?

    Science.gov (United States)

    GUDIEL, ANDREA; Carroll, Joseph; Rowe, David

    2018-01-01

    Authors: Joseph Carroll and David RoweABSTRACT LEO objects are tracked by radar because it works day and night, in all weather. This fits military interest in potentially hostile objects. There is less interest in objects too small to be credible active threats. But accidental hypervelocity impact by even 5-10 mm objects can disable most LEO satellites. Such “cm-class” objects greatly outnumber objects of military interest, and will cause most accidental impact losses.Under good viewing conditions, a sunlit 5mm sphere with 0.15 albedo at 800 km altitude is a 19th magnitude object. A ground-based 0.5m telescope tracking it against a 20 mag/arcsec2 sky can see it in seconds, and provide 1 million such objects in LEO, nearly all debris fragments, mostly cm-class and at 600-1200 km altitude.Maintaining a ~million-item catalog requires a world-wide network of several dozen telescope sites with several telescopes at each site. Each telescope needs a mount capable of ~1,000,000 fast slews/year without wearing out.The paper discusses recent advances that make such a service far more feasible:1. Automated tasking and remote control of distributed telescope networks,2. Direct-drive mounts that can make millions of fast slews without wearing out,3. Telescope optics with low focal curvature that are in focus across large imagers,4. CMOS imagers with 95% peak QE and 1.5e- noise at 2E8 pix/sec readout rates,5. Methods for uncued detection of most lethal LEO debris (eg., >5 mm at 800 km),6. Initial orbit determination using 3 alt-az fixes made during the discovery pass,7. High-speed photometry to infer debris spin axis, to predict drag area changes,8. Better conjunction predictions using explicit modeling of drag area variations.

  7. Converging shocks in elastic-plastic solids.

    Science.gov (United States)

    Ortega, A López; Lombardini, M; Hill, D J

    2011-11-01

    We present an approximate description of the behavior of an elastic-plastic material processed by a cylindrically or spherically symmetric converging shock, following Whitham's shock dynamics theory. Originally applied with success to various gas dynamics problems, this theory is presently derived for solid media, in both elastic and plastic regimes. The exact solutions of the shock dynamics equations obtained reproduce well the results obtained by high-resolution numerical simulations. The examined constitutive laws share a compressible neo-Hookean structure for the internal energy e=e(s)(I(1))+e(h)(ρ,ς), where e(s) accounts for shear through the first invariant of the Cauchy-Green tensor, and e(h) represents the hydrostatic contribution as a function of the density ρ and entropy ς. In the strong-shock limit, reached as the shock approaches the axis or origin r=0, we show that compression effects are dominant over shear deformations. For an isothermal constitutive law, i.e., e(h)=e(h)(ρ), with a power-law dependence e(h) is proportional to ρ(α), shock dynamics predicts that for a converging shock located at r=R(t) at time t, the Mach number increases as M is proportional to [log(1/R)](α), independently of the space index s, where s=2 in cylindrical geometry and 3 in spherical geometry. An alternative isothermal constitutive law with p(ρ) of the arctanh type, which enforces a finite density in the strong-shock limit, leads to M is proportional to R(-(s-1)) for strong shocks. A nonisothermal constitutive law, whose hydrostatic part e(h) is that of an ideal gas, is also tested, recovering the strong-shock limit M is proportional to R(-(s-1)/n(γ)) originally derived by Whitham for perfect gases, where γ is inherently related to the maximum compression ratio that the material can reach, (γ+1)/(γ-1). From these strong-shock limits, we also estimate analytically the density, radial velocity, pressure, and sound speed immediately behind the shock. While the

  8. Shock compression profiles in ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Grady, D.E.; Moody, R.L.

    1996-03-01

    An investigation of the shock compression properties of high-strength ceramics has been performed using controlled planar impact techniques. In a typical experimental configuration, a ceramic target disc is held stationary, and it is struck by plates of either a similar ceramic or by plates of a well-characterized metal. All tests were performed using either a single-stage propellant gun or a two-stage light-gas gun. Particle velocity histories were measured with laser velocity interferometry (VISAR) at the interface between the back of the target ceramic and a calibrated VISAR window material. Peak impact stresses achieved in these experiments range from about 3 to 70 GPa. Ceramics tested under shock impact loading include: Al{sub 2}O{sub 3}, AlN, B{sub 4}C, SiC, Si{sub 3}N{sub 4}, TiB{sub 2}, WC and ZrO{sub 2}. This report compiles the VISAR wave profiles and experimental impact parameters within a database-useful for response model development, computational model validation studies, and independent assessment of the physics of dynamic deformation on high-strength, brittle solids.

  9. Shock-resistant scintillation detector

    International Nuclear Information System (INIS)

    Novak, W.P.

    1979-01-01

    A unique scintillation detector unit is disclosed which employs a special light transfer and reflector means that encases and protects the scintillator crystal against high g forces. The light transfer means comprises a flexible silicon rubber optical material bonded between the crystal and the optical window and having an axial thickness sufficient to allow the scintillator to move axially inside the container under high g forces without destroying the bonds. The reflector means comprises a soft elastic silicone rubber sleeve having a multiplicity of closely arranged tapered protrusions radiating toward and engaging the periphery of the scintillator crystal to cushion shocks effectively and having a reflective material, such as aluminum oxide powder, in the spaces between the protrusions. The reflector means provides improved shock absorption because of the uniform support and cushioning action of the protrusions and also provides the detector with high efficiency. The silicon rubber composition is specially compounded to include a large amount of aluminum oxide which enables the rubber to function effectively as a light reflector

  10. The ''injection problem'' for quasiparallel shocks

    International Nuclear Information System (INIS)

    Zank, G. P.; Rice, W. K. M.; le Roux, J. A.; Cairns, I. H.; Webb, G. M.

    2001-01-01

    For a particle to be accelerated diffusively at a shock by the first-order Fermi acceleration mechanism, the particle must be sufficiently energetic that it can scatter across all the micro- and macrostructure of the shock, experiencing compression between the converging upstream and downstream states. This is the well-known ''injection problem.'' Here the interaction of ions with the ramp of a quasiparallel shock is investigated. Some ions incident on the shock experience specular reflection, caused either by the cross-shock electrostatic potential or by mirroring as the magnetic field is bent and compressed through the ramp. Scattering of reflected ions by self-generated and pre-existing turbulence in the region upstream of the shock then acts to trap backstreaming ions and return them to the ramp, where some experience further reflections. Such repeated reflections and scattering energize a subpopulation of ions up to energies sufficiently large that they can be diffusively shock accelerated. Two ion distributions are considered: pickup ions which are assumed to be described by a shell distribution, are thermal solar wind ions which may be described by a kappa distribution. Injection efficiencies are found analytically to be very high for pickup ions and much lower for thermal solar wind ions, suggesting that this injection mechanism, stochastic reflected ion or SRI acceleration, is a natural precursor for the acceleration of the anomalous cosmic ray component at a quasiparallel shock. While significantly less efficient, SRI acceleration is also viable for thermal solar wind ions described by a kappa distribution

  11. PRECURSORS TO INTERSTELLAR SHOCKS OF SOLAR ORIGIN

    Energy Technology Data Exchange (ETDEWEB)

    Gurnett, D. A.; Kurth, W. S. [University of Iowa, Department of Physics and Astronomy, Iowa City, IA 52242 (United States); Stone, E. C.; Cummings, A. C. [California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125 (United States); Krimigis, S. M.; Decker, R. B. [Applied Physics Laboratory/JHU, 11100 Johns Hopkins Road, Laurel, MD 20723 (United States); Ness, N. F. [Catholic University of America, 620 Michigan Avenue NE, Washington, DC 20064 (United States); Burlaga, L. F., E-mail: donald-gurnett@uiowa.edu [NASA Goddard Space Flight Center, 8800 Greenbelt Road, Greenbelt, MD 20771 (United States)

    2015-08-20

    On or about 2012 August 25, the Voyager 1 spacecraft crossed the heliopause into the nearby interstellar plasma. In the nearly three years that the spacecraft has been in interstellar space, three notable particle and field disturbances have been observed, each apparently associated with a shock wave propagating outward from the Sun. Here, we present a detailed analysis of the third and most impressive of these disturbances, with brief comparisons to the two previous events, both of which have been previously reported. The shock responsible for the third event was first detected on 2014 February 17 by the onset of narrowband radio emissions from the approaching shock, followed on 2014 May 13 by the abrupt appearance of intense electron plasma oscillations generated by electrons streaming outward ahead of the shock. Finally, the shock arrived on 2014 August 25, as indicated by a jump in the magnetic field strength and the plasma density. Various disturbances in the intensity and anisotropy of galactic cosmic rays were also observed ahead of the shock, some of which are believed to be caused by the reflection and acceleration of cosmic rays by the magnetic field jump at the shock, and/or by interactions with upstream plasma waves. Comparisons to the two previous weaker events show somewhat similar precursor effects, although differing in certain details. Many of these effects are very similar to those observed in the region called the “foreshock” that occurs upstream of planetary bow shocks, only on a vastly larger spatial scale.

  12. Corporate Policies with Permanent and Transitory Shocks

    NARCIS (Netherlands)

    J-P. Decamps (Jean-Paul); S. Gryglewicz (Sebastian); E. Morellec (Erwan); S. Villeneuve (Stephane)

    2016-01-01

    textabstractWe model the financing, cash holdings, and hedging policies of a firm facing financing frictions and subject to permanent and transitory cash flow shocks. We show that permanent and transitory shocks generate distinct, sometimes opposite, effects on corporate policies and use the model

  13. Shock dynamics in layered periodic media

    KAUST Repository

    Ketcheson, David I.; Leveque, Randall J.

    2012-01-01

    of shock waves in a one-dimensional periodic layered medium by a computational study of time-reversibility and entropy evolution. We find that periodic layered media tend to inhibit shock formation. For small initial conditions and large impedance variation

  14. Particle acceleration and shock wave structure

    International Nuclear Information System (INIS)

    DRURY, L.O'C.

    1989-01-01

    A significant determinant in the large-scale structure and evolution of strong collisionless shocks under astrophysical conditions is probably the acceleration of charged particles. The reaction of these particles on the dynamical structure of the shock wave is discussed both theoretically and in the light of recent numerical calculations. Astrophysical implications for the evolution of supernova remnants, are considered. (author). 15 refs

  15. Laser shock wave and its applications

    Science.gov (United States)

    Yang, Chaojun; Zhang, Yongkang; Zhou, Jianzhong; Zhang, Fang; Feng, Aixin

    2007-12-01

    The technology of laser shock wave is used to not only surface modification but also metal forming. It can be divided into three parts: laser shock processing, laser shock forming (LSF) and laser peenforming(LPF). Laser shock processing as a surface treatment to metals can make engineering components have a residual compressive stress so that it obviously improves their fatigue strength and stress corrosion performances, while laser shock forming (LSF) is a novel technique that is used in plastic deformation of sheet metal recently and Laser peen forming (LPF) is another new sheet metal forming process presented in recent years. They all can be carried out by a high-power and repetition pulse Nd:Glass laser device made by Jiangsu University. Laser shock technology has characterized of ultrahigh pressure and high strain rate (10 6 - 10 7s -1). Now, for different materials, we are able to form different metals to contours and shapes and simultaneity leave their surfaces in crack-resistant compressive stress state. The results show that the technology of laser shock wave can strengthen surface property and prolong fatigue life and especially can deform metals to shapes that could not be adequately made using conventional methods. With the development of the technology of laser shock wave, the applied fields of laser will become greater and greater.

  16. Introduction to Shock Waves and Shock Wave Research

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, William Wyatt [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-02-02

    M-9 and a number of other organizations at LANL and elsewhere study materials in dynamic processes. Often, this is described as “shock wave research,” but in reality is broader than is implied by that term. Most of our work is focused on dynamic compression and associated phenomena, but you will find a wide variety of things we do that, while related, are not simple compression of materials, but involve a much richer variety of phenomena. This tutorial will introduce some of the underlying physics involved in this work, some of the more common types of phenomena we study, and common techniques. However, the list will not be exhaustive by any means.

  17. Comparative influence of dose rate and radiation nature, on lethality after big mammals irradiation

    International Nuclear Information System (INIS)

    Destombe, C.; Le Fleche, Ph.; Grasseau, A.; Reynal, A.

    1997-01-01

    For the same dose and the 30 days lethality as biological criterion, the dose rate influence is more important than the radiation nature on the results of an big mammals total body irradiation. (authors)

  18. Anti-Cancer Drug Discovery Using Synthetic Lethal Chemogenetic (SLC) Analysis

    National Research Council Canada - National Science Library

    Bellows, David S

    2006-01-01

    I am developing a novel cell-based small-molecule screening approach that can identify inhibitors of any non-essential protein function through a surrogate synthetic lethal phenotype in the baker's...

  19. Anti-Cancer Drug Discovery Using Synthetic Lethal Chemogenetic (SLC) Analysis

    National Research Council Canada - National Science Library

    Bellows, David S

    2004-01-01

    I am developing a novel cell-based small-molecule screening approach that can identify inhibitors of any non-essential protein function through a surrogate synthetic lethal phenotype in the baker's...

  20. 76 FR 6054 - Use of Less-Than-Lethal Force: Delegation

    Science.gov (United States)

    2011-02-03

    ... report any medical problems encountered by subjects being subdued and arrested, and no medical problems.... Therefore, for accuracy in terminology, we replace the term ``non-lethal'' with the more accurate term...

  1. The Effects of Posture, Body Armor and Other Equipment on Rifleman Lethality

    National Research Council Canada - National Science Library

    Kramlich, Gary R., II

    2005-01-01

    ...? This study quantifies the effects of Soldier equipment on lethality through multi-factor logistic regression using data from range experiments with the 1st Brigade, 1st Infantry Division (Mechanized...

  2. Lethal and Sublethal Effects of Fenpropathrin on the Biological Performance of Scolothrips longicornis (Thysanoptera: Thripidae)

    DEFF Research Database (Denmark)

    Pakyari, Hajar; Enkegaard, Annie

    2013-01-01

    Determination of negative nontarget effects of pesticides on beneficial organisms by measuring only lethal effects is likely to underestimate effects of sublethal doses. In this study, the sublethal effects of fenpropathrin on the predatory thrips Scolothrips longicornis Priesner (Thysanoptera: T...

  3. Recurrent late cardiac tamponade following cardiac surgery : a deceiving and potentially lethal complication

    NARCIS (Netherlands)

    Harskamp, Ralf E.; Meuzelaar, Jacobus J.

    2010-01-01

    Background - Cardiac tamponade, characterized by inflow obstruction of the heart chambers by extracardiac compression, is a potentially lethal complication following cardiac surgery. Case report - We present a case of recurrent cardiac tamponade following valve surgery. At first presentation,

  4. Recurrent late cardiac tamponade following cardiac surgery: a deceiving and potentially lethal complication

    NARCIS (Netherlands)

    Harskamp, Ralf E.; Meuzelaar, Jacobus J.

    2010-01-01

    Cardiac tamponade, characterized by inflow obstruction of the heart chambers by extracardiac compression, is a potentially lethal complication following cardiac surgery. We present a case of recurrent cardiac tamponade following valve surgery. At first presentation, diagnosis was delayed because of

  5. Variability in mutational fitness effects prevents full lethal transitions in large quasispecies populations

    Science.gov (United States)

    Sardanyés, Josep; Simó, Carles; Martínez, Regina; Solé, Ricard V.; Elena, Santiago F.

    2014-04-01

    The distribution of mutational fitness effects (DMFE) is crucial to the evolutionary fate of quasispecies. In this article we analyze the effect of the DMFE on the dynamics of a large quasispecies by means of a phenotypic version of the classic Eigen's model that incorporates beneficial, neutral, deleterious, and lethal mutations. By parameterizing the model with available experimental data on the DMFE of Vesicular stomatitis virus (VSV) and Tobacco etch virus (TEV), we found that increasing mutation does not totally push the entire viral quasispecies towards deleterious or lethal regions of the phenotypic sequence space. The probability of finding regions in the parameter space of the general model that results in a quasispecies only composed by lethal phenotypes is extremely small at equilibrium and in transient times. The implications of our findings can be extended to other scenarios, such as lethal mutagenesis or genomically unstable cancer, where increased mutagenesis has been suggested as a potential therapy.

  6. Shock loading predictions from application of indicial theory to shock-turbulence interactions

    Science.gov (United States)

    Keefe, Laurence R.; Nixon, David

    1991-01-01

    A sequence of steps that permits prediction of some of the characteristics of the pressure field beneath a fluctuating shock wave from knowledge of the oncoming turbulent boundary layer is presented. The theory first predicts the power spectrum and pdf of the position and velocity of the shock wave, which are then used to obtain the shock frequency distribution, and the pdf of the pressure field, as a function of position within the interaction region. To test the validity of the crucial assumption of linearity, the indicial response of a normal shock is calculated from numerical simulation. This indicial response, after being fit by a simple relaxation model, is used to predict the shock position and velocity spectra, along with the shock passage frequency distribution. The low frequency portion of the shock spectra, where most of the energy is concentrated, is satisfactorily predicted by this method.

  7. Shock-induced devolatilization of calcite

    Science.gov (United States)

    Boslough, M. B.; Ahrens, T. J.; Vizgirda, J.; Becker, R. H.; Epstein, S.

    1982-01-01

    Experimental measurements of the release adiabats by Vizgirda (1981) indicate that substantial vaporization takes place upon release from shock pressures of 37 GPa for calcite and 14 GPa for aragonite. The present investigation includes the first controlled partial vaporization experiments on calcite. The experiments were conducted to test the predictions of the release adiabat experiments. The quantities of the gaseous species produced from shocked calcite and their carbon and oxygen isotopic compositions were determined, and the shock-induced effect on the Mn(2+) electron spin resonance spectrum in the shock-recovered calcite was observed. On the basis of the obtained results, it is concluded that shock stresses at the 17-18 GPa level give rise to volatilization of 0.03-0.3 (mole) percent of calcite to CO2 and CO. The devolatilization of calcite occurs at low pressure at significantly lower entropy densities than predicted on the basis of thermodynamic continuum models.

  8. Shock waves in helium at low temperatures

    International Nuclear Information System (INIS)

    Liepmann, H.W.; Torczynski, J.R.

    1986-01-01

    Results are reported from studies of the properties of low temperature He-4 using shock waves as a probe. Ideal shock tube theory is used to show that sonic speeds of Mach 40 are attainable in He at 300 K. Viscosity reductions at lower temperatures minimize boundary layer effects at the side walls. A two-fluid model is described to account for the phase transition which He undergoes at temperatures below 2.2 K, after which the quantum fluid (He II) and the normal compressed superfluid (He I) coexist. Analytic models are provided for pressure-induced shocks in He I and temperature-induced shock waves (called second sound) which appear in He II. The vapor-fluid interface of He I is capable of reflecting second and gasdynamic sound shocks, which can therefore be used as probes for studying phase transitions between He I and He II. 17 references

  9. Analytical extension of curved shock theory

    Science.gov (United States)

    Emanuel, G.

    2018-03-01

    Curved shock theory (CST) is limited to shock waves in a steady, two-dimensional or axisymmetric (2-Ax) flow of a perfect gas. A unique feature of CST is its use of intrinsic coordinates that result in an elegant and useful formulation for flow properties just downstream of a shock. For instance, the downstream effect of upstream vorticity, shock wave curvature, and the upstream pressure gradient along a streamline is established. There have been several attempts to extend CST, as mentioned in the text. Removal of the steady, 2-Ax, and perfect gas limitations, singly or in combination, requires an appropriate formulation of the shock wave's jump relations and the intrinsic coordinate Euler equations. Issues discussed include flow plane versus osculating plane, unsteady flow, vorticity, an imperfect gas, etc. The extension of CST utilizes concepts from differential geometry, such as the osculating plane, streamline torsion, and the Serret-Frenet equations.

  10. 28th International Symposium on Shock Waves

    CERN Document Server

    2012-01-01

    The University of Manchester hosted the 28th International Symposium on Shock Waves between 17 and 22 July 2011. The International Symposium on Shock Waves first took place in 1957 in Boston and has since become an internationally acclaimed series of meetings for the wider Shock Wave Community. The ISSW28 focused on the following areas: Blast Waves, Chemically Reacting Flows, Dense Gases and Rarefied Flows, Detonation and Combustion, Diagnostics, Facilities, Flow Visualisation, Hypersonic Flow, Ignition, Impact and Compaction, Multiphase Flow, Nozzle Flow, Numerical Methods, Propulsion, Richtmyer-Meshkov, Shockwave Boundary Layer Interaction, Shock Propagation and Reflection, Shock Vortex Interaction, Shockwave Phenomena and Applications, as well as Medical and Biological Applications. The two Volumes contain the papers presented at the symposium and serve as a reference for the participants of the ISSW 28 and individuals interested in these fields.

  11. Barrier experiment: Shock initiation under complex loading

    Energy Technology Data Exchange (ETDEWEB)

    Menikoff, Ralph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-01-12

    The barrier experiments are a variant of the gap test; a detonation wave in a donor HE impacts a barrier and drives a shock wave into an acceptor HE. The question we ask is: What is the trade-off between the barrier material and threshold barrier thickness to prevent the acceptor from detonating. This can be viewed from the perspective of shock initiation of the acceptor subject to a complex pressure drive condition. Here we consider key factors which affect whether or not the acceptor undergoes a shock-to-detonation transition. These include the following: shock impedance matches for the donor detonation wave into the barrier and then the barrier shock into the acceptor, the pressure gradient behind the donor detonation wave, and the curvature of detonation front in the donor. Numerical simulations are used to illustrate how these factors affect the reaction in the acceptor.

  12. Semi-lethal high temperature and heat tolerance of eight Camellia species

    OpenAIRE

    He, XY; Ye, H; Ma, JL; Zhang, RQ; Chen, GC; Xia, YY

    2012-01-01

    Annual leaf segments of eight Camellia species were used to study the heat tolerance by an electrical conductivity method, in combination with a Logistic equation to ascertain the semi-lethal high temperature by fitting the cell injury rate curve. Te relationship between the processing temperature and the cell injury rate in Camellia showed a typical "S" shaped curve, following the Logistic model. Te correlation coeficient was above 0.95. Te semi-lethal high temperature LT50 of the eight Came...

  13. Synthetic Lethal Therapeutic Approaches for ARID1A-Mutated Ovarian Cancer

    Science.gov (United States)

    2017-10-01

    Award Number: W81XWH-16-1-0496 TITLE: Synthetic lethal therapeutic approaches for ARID1A-mutated ovarian cancer PRINCIPAL INVESTIGATOR: Rugang...AND SUBTITLE Synthetic lethal therapeutic approaches for ARID1A-mutated ovarian cancer 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH-16-1-0496 5c...Release; Distribution Unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT Epithelial ovarian cancer (EOC) is the leading cause of death among gynecological

  14. Lethality of patients with rheumatoid arthritis depending on adalimumab administration: imitation modeling

    Directory of Open Access Journals (Sweden)

    D V Goryachev

    2009-01-01

    Full Text Available Lethality of pts with rheumatoid arthritis (RA exceeds mortality values in general population. Possibility of disease modifying anti-rheumatic drugs (DMARD influence on RA pts lethality has been widely discussed lately in scientific works. Objective. To determine possible lethality diminishment in Russian population of RA pts with one of biological drugs TNFα antagonist adalimumab. Material and methods. Model construction is based on the fact of lethality dependence on pt functional state assessed by HAQ. Model simulating progression of functional disability in pts with RA visiting medical institutions of Russia was made (RAISER study. 3 model variants for imitation of consecutive change of DMARDs including adalimumab were done. First consecution assessed DMARD change in the next chain: adalimumab-methotrexate-sulfasalazine-leflunomide-azathioprine-cyclosporine-palliative therapy. Second consecution: adalimumab administration after failure of first 3 DMARDs. Third consecution considered only change of synthetic DMARDs without adalimumab inclusion. Model imitated participation of 3000 pts in every consecution. Prognosis horizon was 12 years. Age of pts and initial HAQ distribution were get from results of epidemiological RAISER study. Calculation was done on the base of elevation of standardized lethality level (SLL in population of RA pts in average from 135% to 300%. SLL values from 80 to 320% were used depending on functional disability degree with converting to Russian values of age-specific lethality coefficient for 1999. Results. Lethality in treatment consecutions including adalimumab was significantly lower. To the end of 12th year in group not using adalimumab, using it at once and using it after 376 DMARDs respectively 65,1%, 71,6% and 71,1% of pts were still alive. Conclusion. Significant decrease of lethality with adalimumab inclusion in consecution of DMARD change during treatment of RA pts was demonstrated with imitation modeling

  15. Recovery from UV-induced potentially lethal damage in systemic lupus erythematosus skin fibroblasts

    Energy Technology Data Exchange (ETDEWEB)

    Zamansky, G B

    1986-08-01

    The repair of ultraviolet light-induced potentially lethal damage was investigated in density-inhibited skin fibroblast cell strains derived from patients with systemic lupus erythematosus. The effect of exposure to polychromatic ultraviolet light composed of environmentally relevant wavelengths or to the more commonly studied, short wavelength (254 nm) ultraviolet light was studied. Systemic lupus erythematosus cells, which are hypersensitive to ultraviolet light under growth promoting conditions, were able to repair potentially lethal damage as well as normal cells.

  16. Recovery from UV-induced potentially lethal damage in systemic lupus erythematosus skin fibroblasts

    International Nuclear Information System (INIS)

    Zamansky, G.B.

    1986-01-01

    The repair of ultraviolet light-induced potentially lethal damage was investigated in density-inhibited skin fibroblast cell strains derived from patients with systemic lupus erythematosus. The effect of exposure to polychromatic ultraviolet light composed of environmentally relevant wavelengths or to the more commonly studied, short wavelength (254 nm) ultraviolet light was studied. Systemic lupus erythematosus cells, which are hypersensitive to ultraviolet light under growth promoting conditions, were able to repair potentially lethal damage as well as normal cells. (author)

  17. Non-Lethal Weapons: A Technology Gap or Lack or Available Systems, Training, and Proper Application

    Science.gov (United States)

    2016-06-10

    102-104. 31 Ibid., 103-104. 32 Michael Wines , “The Aftermath in Moscow: Post-Mortem in Moscow; Russia Names Drug in Raid, Defending Use,” New York...during the past three decades have increased awareness of the benefit of non- lethal options, but increased advocacy within the services has not led to a...during the execution of suitable missions that could benefit from less than lethal technology. Research and Development Once the directorate

  18. Small-Scale Shock Testing of Propellants and Ingredients

    National Research Council Canada - National Science Library

    Dawley, S

    2004-01-01

    .... The use of small-scale gap testing to evaluate the shock sensitivity of individual propellant ingredients and propellant formulations is a valuable method for experimentally establishing shock...

  19. Surface instabilities in shock loaded granular media

    Science.gov (United States)

    Kandan, K.; Khaderi, S. N.; Wadley, H. N. G.; Deshpande, V. S.

    2017-12-01

    The initiation and growth of instabilities in granular materials loaded by air shock waves are investigated via shock-tube experiments and numerical calculations. Three types of granular media, dry sand, water-saturated sand and a granular solid comprising PTFE spheres were experimentally investigated by air shock loading slugs of these materials in a transparent shock tube. Under all shock pressures considered here, the free-standing dry sand slugs remained stable while the shock loaded surface of the water-saturated sand slug became unstable resulting in mixing of the shocked air and the granular material. By contrast, the PTFE slugs were stable at low pressures but displayed instabilities similar to the water-saturated sand slugs at higher shock pressures. The distal surfaces of the slugs remained stable under all conditions considered here. Eulerian fluid/solid interaction calculations, with the granular material modelled as a Drucker-Prager solid, reproduced the onset of the instabilities as seen in the experiments to a high level of accuracy. These calculations showed that the shock pressures to initiate instabilities increased with increasing material friction and decreasing yield strain. Moreover, the high Atwood number for this problem implied that fluid/solid interaction effects were small, and the initiation of the instability is adequately captured by directly applying a pressure on the slug surface. Lagrangian calculations with the directly applied pressures demonstrated that the instability was caused by spatial pressure gradients created by initial surface perturbations. Surface instabilities are also shown to exist in shock loaded rear-supported granular slugs: these experiments and calculations are used to infer the velocity that free-standing slugs need to acquire to initiate instabilities on their front surfaces. The results presented here, while in an idealised one-dimensional setting, provide physical understanding of the conditions required to

  20. Reproductive-phase and interphase lethal cell damage after irradiation and treatment with cytostatics

    International Nuclear Information System (INIS)

    Hagemann, G.

    1979-01-01

    After X-ray irradiation of manual cells, two lethal fractions occur due to reproductive and interphase death under low and high radiation doses. The damage kinetics on which this fact is based is compared with hypothetical tumour frequencies and leucemia induction caused in experiments. The reproductive-lethal damage can be manifested by means of colony size spectrometry, with the median colony size class differences (MCD) serving as measure for the damage found. The simultaneous effects of the cytostatics BLEOMYCIN or ICRF 159 and X-rays on reproductive lethal and interphase-lethal damage are measured by means of MCD and survival fraction, and the additive and intensifying effect' is judged with the help of suitably defined terms. This shows that the clinically used ICRF 159 has an additive effect on interphase-lethal and a sub-additive effect on reproductive-lethal cell damage. Thus, favourable results may be expected for the electivity factor in fractionated irradiation and with regard to delayed damage in healthy tissue. (orig.) 891 MG/orig. 892 RDG [de

  1. Materials Applications for Non-Lethal: Aqueous Foams

    International Nuclear Information System (INIS)

    GOOLSBY, TOMMY D.; SCOTT, STEVEN H.

    1999-01-01

    High expansion aqueous foam is an aggregation of bubbles that has the appearance of soap suds and is used to isolate individuals both visually and acoustically. It was developed in the 1920's in England to fight coal mine fires and has been widely used since for fire fighting and dust suppression. It was developed at Sandia National Laboratories (SNL) in the 1970's for nuclear safeguards and security applications. In the mid-1990s, the National Institute of Justice (NIJ), the research arm of the Department of Justice, began a project with SNL to determine the applicability of high expansion aqueous foam for correctional applications. NIJ funded the project as part of its search for new and better less-than-lethal weapons for responding to violent and dangerous individuals, where other means of force could lead to serious injuries. The phase one objectives of the project were to select a low-to-no toxicity foam concentrate (foaming agent) with physical characteristics suited for use in a single cell or large prison disturbances, and to determine if the selected foam concentrate could serve as a carrier for Oleoresin Capsicum (OC) irritant. The phase two objectives were to conduct an extensive toxicology review of the selected foam concentrate and OC irritant, and to conduct respiration simulation experiments in the selected high expansion aqueous foam. The phase three objectives were to build a prototype individual cell aqueous foam system and to study the feasibility of aqueous foams for large prison facility disturbances. The phase four and five objectives were to use the prototype system to do large scale foam physical characteristics testing of the selected foam concentrate, and to have the prototype single cell system further evaluated by correctional representatives. Prison rather than street scenarios were evaluated as the first and most likely place for using the aqueous foam since prisons have recurrent incidents where officers and inmates might be

  2. Materials Applications for Non-Lethal: Aqueous Foams

    Energy Technology Data Exchange (ETDEWEB)

    GOOLSBY,TOMMY D.; SCOTT,STEVEN H.

    1999-09-15

    High expansion aqueous foam is an aggregation of bubbles that has the appearance of soap suds and is used to isolate individuals both visually and acoustically. It was developed in the 1920's in England to fight coal mine fires and has been widely used since for fire fighting and dust suppression. It was developed at Sandia National Laboratories (SNL) in the 1970's for nuclear safeguards and security applications. In the mid-1990s, the National Institute of Justice (NIJ), the research arm of the Department of Justice, began a project with SNL to determine the applicability of high expansion aqueous foam for correctional applications. NIJ funded the project as part of its search for new and better less-than-lethal weapons for responding to violent and dangerous individuals, where other means of force could lead to serious injuries. The phase one objectives of the project were to select a low-to-no toxicity foam concentrate (foaming agent) with physical characteristics suited for use in a single cell or large prison disturbances, and to determine if the selected foam concentrate could serve as a carrier for Oleoresin Capsicum (OC) irritant. The phase two objectives were to conduct an extensive toxicology review of the selected foam concentrate and OC irritant, and to conduct respiration simulation experiments in the selected high expansion aqueous foam. The phase three objectives were to build a prototype individual cell aqueous foam system and to study the feasibility of aqueous foams for large prison facility disturbances. The phase four and five objectives were to use the prototype system to do large scale foam physical characteristics testing of the selected foam concentrate, and to have the prototype single cell system further evaluated by correctional representatives. Prison rather than street scenarios were evaluated as the first and most likely place for using the aqueous foam since prisons have recurrent incidents where officers and inmates might

  3. Scopolamine methylbromide mitigates radiation induced damage and lethality in zebrafish

    International Nuclear Information System (INIS)

    Shrivastava, Nitisha; Joshi, Jayadev; Ghosh, Subhajit; Dimri, Manali; Prem Kumar, Indracanti; Sehgal, Neeta

    2014-01-01

    In view of the strategic importance radiation countermeasures hold, the present study was undertaken to screen a collection of small molecule clinical compounds for possible radioprotective action using zebrafish as a model system. Preliminary screening in developing zebrafish embryos (24 hour post fertilization, (hpf)) using damage manifestations and survival as end point identified scopolamine methylbromide (SMB), a muscarinic receptor antagonist, as a potential radiomitigator. It was found to be optimal (60% survival advantage after 6 th post irradiation day) at a dose of 80 μM when added 3 h post 20 Gy exposure. Mechanistic studies suggested that SMB though exhibited no significant antioxidant potential, but was found to limit radiation induced apoptosis (pre G1 population) quantified through flow cytometry (6 and 5% reduction after 8 or 24 h after treatments) and annexin V staining (8% reduction). Further, quantitative analysis, using caspase 3 assay, revealed a 2.46 fold increase in apoptosis in irradiated group and treatment of irradiated zebrafish embryos with SMB led to a significant reduction in global apoptosis (1.7 fold; p<0.05) when compared to irradiated group. In silico studies based on structural and functional similarity with known radioprotectors suggested similarities with atropine, a known anti-inflammatory agent with muscarinic antagonism and radioprotective potential. In view of this SMB was tested, in silico, for possible anti-inflammatory action. Molecular docking studies revealed that SMB interacts (B.E-8.0 Kcal/mole) with cycloxygenase-2 (COX-2). In lieu of this, anti-inflammation activity was assessed through ChIN (chemically induced inflammation) method in 3 dpf (days post fertilization) embryos and SMB was found to significantly inhibit inflammation at all doses studied from 20-200 μM at 3 and 6 hpi (hours post inflammation). Overall the result suggests that scopolamine methylbromide mitigates radiation induced injury and lethality in

  4. Gene knockout of the KCNJ8-encoded Kir6.1 K(ATP) channel imparts fatal susceptibility to endotoxemia.

    Science.gov (United States)

    Kane, Garvan C; Lam, Chen-Fuh; O'Cochlain, Fearghas; Hodgson, Denice M; Reyes, Santiago; Liu, Xiao-Ke; Miki, Takashi; Seino, Susumu; Katusic, Zvonimir S; Terzic, Andre

    2006-11-01

    Sepsis, the systemic inflammatory response to infection, imposes a high demand for bodily adaptation, with the cardiovascular response a key determinant of outcome. The homeostatic elements that secure cardiac tolerance in the setting of the sepsis syndrome are poorly understood. Here, in a model of acute septic shock induced by endotoxin challenge with Escherichia coli lipopolysaccharide (LPS), knockout of the KCNJ8 gene encoding the vascular Kir6.1 K(ATP) channel pore predisposed to an early and profound survival disadvantage. The exaggerated susceptibility provoked by disruption of this stress-responsive sensor of cellular metabolism was linked to progressive deterioration in cardiac activity, ischemic myocardial damage, and contractile dysfunction. Deletion of KCNJ8 blunted the responsiveness of coronary vessels to cytokine- or metabolic-mediated vasodilation necessary to support myocardial perfusion in the wild-type (WT), creating a deficit in adaptive response in the Kir6.1 knockout. Application of a K(ATP) channel opener drug improved survival in the endotoxic WT but had no effect in the Kir6.1 knockout. Restoration of the dilatory capacity of coronary vessels was required to rescue the Kir6.1 knockout phenotype and reverse survival disadvantage in lethal endotoxemia. Thus, the Kir6.1-containing K(ATP) channel, by coupling vasoreactivity with metabolic demand, provides a vital feedback element for cardiovascular tolerance in endotoxic shock.

  5. A lethal ovitrap-based mass trapping scheme for dengue control in Australia: I. Public acceptability and performance of lethal ovitraps.

    Science.gov (United States)

    Ritchie, S A; Rapley, L P; Williams, C; Johnson, P H; Larkman, M; Silcock, R M; Long, S A; Russell, R C

    2009-12-01

    We report on the first field evaluation of the public acceptability and performance of two types of lethal ovitrap (LO) in three separate trials in Cairns, Australia. Health workers were able to set standard lethal ovitraps (SLOs) in 75 and 71% of premise yards in the wet and dry season, respectively, and biodegradable lethal ovitraps (BLOs) in 93% of yards. Public acceptance, measured as retention of traps by residents, was high for both trap types, with porous (grass, soil and mulch) versus solid (tiles, concrete, wood and stone) substrates. The SLOs and the BLOs were readily acceptable to ovipositing Aedes aegypti L. (Diptera: Culicidae); the mean number of eggs/trap was 6 and 15, for the dry season and wet season SLO trial, respectively, and 15 for the BLO wet season trial. Indeed, 84-94% of premise yards had egg positive SLOs or BLOs. A high percentage of both wet and dry season SLOs (29 and 70%, respectively) and BLOs (62%) that were dry after 4 weeks were egg positive, indicating the traps had functioned. Lethal strips from SLOs and BLOs that had been exposed for 4 weeks killed 83 and 74%, respectively, of gravid Ae. aegypti in laboratory assays. These results indicate that mass trapping schemes using SLOs and BLOs are not rejected by the public and effectively target gravid Ae. aegypti. The impact of the interventions on mosquito populations is described in a companion paper.

  6. [High-dosage glucocorticoid therapy in acute heart infarct and in cardiogenic shock].

    Science.gov (United States)

    Krosch, H; Schäbitz, J

    1977-11-15

    40 patients with cardiogenic shock in consequence of contractility insufficiency of the heart were treated with high doses of prednisolon for short time. In 10 cases a good result of the treatment was to be seen so that the lethality quota was smaller than that of a reference group of the same age. The pharmacodynamic effect is seen in an improvement of the micro-circulation by a peripheric vasodilatation. 10 patients with acute myocardial infarction got a therapy with glucocorticoid combined with a treatment with anti-coagulants during the first both weeks. In this connection modern experimental examinations of animals are discussed which showed that glucocorticoides improve the anoxy tolerance of the heart muscle cell.

  7. Effects of Atwood number on shock focusing in shock-cylinder interaction

    Science.gov (United States)

    Ou, Junfeng; Ding, Juchun; Luo, Xisheng; Zhai, Zhigang

    2018-02-01

    The evolution of shock-accelerated heavy-gas cylinder surrounded by the air with different Atwood numbers (A_t=0.28, 0.50, 0.63) is investigated, concentrating on shock focusing and jet formation. Experimentally, a soap film technique is used to generate an ideal two-dimensional discontinuous gas cylinder with a clear surface, which can guarantee the observation of shock wave movements inside the cylinder. Different Atwood numbers are realized by different mixing ratios of SF_6 and air inside the cylinder. A high-speed schlieren system is adopted to capture the shock motions and jet morphology. Numerical simulations are also performed to provide more information. The results indicate that an inward jet is formed for low Atwood numbers, while an outward jet is generated for high Atwood numbers. Different Atwood numbers will lead to the differences in the relative velocities between the incident shock and the refraction shock, which ultimately results in the differences in shock competition near the downstream pole. The morphology and feature of the jet are closely associated with the position and intensity of shock focusing. The pressure and vorticity contours indicate that the jet formation should be attributed to the pressure pulsation caused by shock focusing, and the jet development is ascribed to the vorticity induction. Finally, a time ratio proposed in the previous work for determining the shock-focusing type is verified by experiments.

  8. Shock Mechanism Analysis and Simulation of High-Power Hydraulic Shock Wave Simulator

    Directory of Open Access Journals (Sweden)

    Xiaoqiu Xu

    2017-01-01

    Full Text Available The simulation of regular shock wave (e.g., half-sine can be achieved by the traditional rubber shock simulator, but the practical high-power shock wave characterized by steep prepeak and gentle postpeak is hard to be realized by the same. To tackle this disadvantage, a novel high-power hydraulic shock wave simulator based on the live firing muzzle shock principle was proposed in the current work. The influence of the typical shock characteristic parameters on the shock force wave was investigated via both theoretical deduction and software simulation. According to the obtained data compared with the results, in fact, it can be concluded that the developed hydraulic shock wave simulator can be applied to simulate the real condition of the shocking system. Further, the similarity evaluation of shock wave simulation was achieved based on the curvature distance, and the results stated that the simulation method was reasonable and the structural optimization based on software simulation is also beneficial to the increase of efficiency. Finally, the combination of theoretical analysis and simulation for the development of artillery recoil tester is a comprehensive approach in the design and structure optimization of the recoil system.

  9. A Prognostic Model for Development of Profound Shock among Children Presenting with Dengue Shock Syndrome.

    Directory of Open Access Journals (Sweden)

    Phung Khanh Lam

    Full Text Available To identify risk factors and develop a prediction model for the development of profound and recurrent shock amongst children presenting with dengue shock syndrome (DSS.We analyzed data from a prospective cohort of children with DSS recruited at the Paediatric Intensive Care Unit of the Hospital for Tropical Disease in Ho Chi Minh City, Vietnam. The primary endpoint was "profound DSS", defined as ≥2 recurrent shock episodes (for subjects presenting in compensated shock, or ≥1 recurrent shock episodes (for subjects presenting initially with decompensated/hypotensive shock, and/or requirement for inotropic support. Recurrent shock was evaluated as a secondary endpoint. Risk factors were pre-defined clinical and laboratory variables collected at the time of presentation with shock. Prognostic model development was based on logistic regression and compared to several alternative approaches.The analysis population included 1207 children of whom 222 (18% progressed to "profound DSS" and 433 (36% had recurrent shock. Independent risk factors for both endpoints included younger age, earlier presentation, higher pulse rate, higher temperature, higher haematocrit and, for females, worse hemodynamic status at presentation. The final prognostic model for "profound DSS" showed acceptable discrimination (AUC=0.69 for internal validation and calibration and is presented as a simple score-chart.Several risk factors for development of profound or recurrent shock among children presenting with DSS were identified. The score-chart derived from the prognostic models should improve triage and management of children presenting with DSS in dengue-endemic areas.

  10. Heat shock proteins of higher plants

    International Nuclear Information System (INIS)

    Key, J.L.; Lin, C.Y.; Chen, Y.M.

    1981-01-01

    The pattern of protein synthesis changes rapidly and dramatically when the growth temperture of soybean seedling tissue is increased from 28 0 C (normal) to about 40 0 C (heat shock). The synthesis of normal proteins is greatly decreased and a new set of proteins, heat shock proteins, is induced. The heat shock proteins of soybean consist of 10 new bands on one-dimensional NaDodSO 4 gels; a more complex pattern is observed on two-dimensional gels. when the tissue is returned to 28 0 C after 4 hr at 40 0 C, there is progressive decline in the synthesis of heat shock proteins and reappearance of a normal pattern of synthesis by 3 or 4 hr. In vitro translation of poly(A) + RNAs isolated from tissued grown at 28 and 40 0 C shows that the heat shock proteins are translated from a ndw set of mRNAs induced at 40 0 C; furthermore, the abundant class mRNAs for many of the normal proteins persist even though they are translated weakly (or not at all) in vivo at 40 or 42.5 0 C. The heat shock response in soybean appears similar to the much-studied heat shock phenomenon in Drosophila

  11. Overview of shock waves in medicine

    Science.gov (United States)

    Cleveland, Robin O.

    2003-10-01

    A brief overview of three applications of shock waves is presented. Shock wave lithotripsy (SWL) has been in clinical use for more than 20 years. In the United States it is used to treat more than 80% of kidney stone cases and has wide acceptance with patients because it is a noninvasive procedure. Despite SWLs enormous success there is no agreement on how shock waves comminute stones. There is also a general acceptance that shock waves lead to trauma to the soft tissue of the kidney. Yet there has been little forward progress in developing lithotripters which provide comminution with less side-effects, indeed the original machine is still considered the gold standard. The last decade has seen the advent of new shock wave devices for treating principally musculoskeletal indications, such as plantar fasciitis, tennis elbow, and bone fractures that do not heal. This is referred to as shock wave therapy (SWT). The mechanisms by which SWT works are even less well understood than SWL and the consequences of bioeffects have also not been studied in detail. Shock waves have also been shown to be effective at enhancing drug delivery into cells and assisting with gene transfection. [Work partially supported by NIH.

  12. Structure of Energetic Particle Mediated Shocks Revisited

    International Nuclear Information System (INIS)

    Mostafavi, P.; Zank, G. P.; Webb, G. M.

    2017-01-01

    The structure of collisionless shock waves is often modified by the presence of energetic particles that are not equilibrated with the thermal plasma (such as pickup ions [PUIs] and solar energetic particles [SEPs]). This is relevant to the inner and outer heliosphere and the Very Local Interstellar Medium (VLISM), where observations of shock waves (e.g., in the inner heliosphere) show that both the magnetic field and thermal gas pressure are less than the energetic particle component pressures. Voyager 2 observations revealed that the heliospheric termination shock (HTS) is very broad and mediated by energetic particles. PUIs and SEPs contribute both a collisionless heat flux and a higher-order viscosity. We show that the incorporation of both effects can completely determine the structure of collisionless shocks mediated by energetic ions. Since the reduced form of the PUI-mediated plasma model is structurally identical to the classical cosmic ray two-fluid model, we note that the presence of viscosity, at least formally, eliminates the need for a gas sub-shock in the classical two-fluid model, including in that regime where three are possible. By considering parameters upstream of the HTS, we show that the thermal gas remains relatively cold and the shock is mediated by PUIs. We determine the structure of the weak interstellar shock observed by Voyager 1 . We consider the inclusion of the thermal heat flux and viscosity to address the most general form of an energetic particle-thermal plasma two-fluid model.

  13. Impaired Fracture Healing after Hemorrhagic Shock

    Directory of Open Access Journals (Sweden)

    Philipp Lichte

    2015-01-01

    Full Text Available Impaired fracture healing can occur in severely injured patients with hemorrhagic shock due to decreased soft tissue perfusion after trauma. We investigated the effects of fracture healing in a standardized pressure controlled hemorrhagic shock model in mice, to test the hypothesis that bleeding is relevant in the bone healing response. Male C57/BL6 mice were subjected to a closed femoral shaft fracture stabilized by intramedullary nailing. One group was additionally subjected to pressure controlled hemorrhagic shock (HS, mean arterial pressure (MAP of 35 mmHg for 90 minutes. Serum cytokines (IL-6, KC, MCP-1, and TNF-α were analyzed 6 hours after shock. Fracture healing was assessed 21 days after fracture. Hemorrhagic shock is associated with a significant increase in serum inflammatory cytokines in the early phase. Histologic analysis demonstrated a significantly decreased number of osteoclasts, a decrease in bone quality, and more cartilage islands after hemorrhagic shock. μCT analysis showed a trend towards decreased bone tissue mineral density in the HS group. Mechanical testing revealed no difference in tensile failure. Our results suggest a delay in fracture healing after hemorrhagic shock. This may be due to significantly diminished osteoclast recruitment. The exact mechanisms should be studied further, particularly during earlier stages of fracture healing.

  14. Structure of Energetic Particle Mediated Shocks Revisited

    Energy Technology Data Exchange (ETDEWEB)

    Mostafavi, P.; Zank, G. P. [Department of Space Science, University of Alabama in Huntsville, Huntsville, AL 35899 (United States); Webb, G. M. [Center for Space Plasma and Aeronomic Research (CSPAR), University of Alabama in Huntsville, Huntsville, AL 35899 (United States)

    2017-05-20

    The structure of collisionless shock waves is often modified by the presence of energetic particles that are not equilibrated with the thermal plasma (such as pickup ions [PUIs] and solar energetic particles [SEPs]). This is relevant to the inner and outer heliosphere and the Very Local Interstellar Medium (VLISM), where observations of shock waves (e.g., in the inner heliosphere) show that both the magnetic field and thermal gas pressure are less than the energetic particle component pressures. Voyager 2 observations revealed that the heliospheric termination shock (HTS) is very broad and mediated by energetic particles. PUIs and SEPs contribute both a collisionless heat flux and a higher-order viscosity. We show that the incorporation of both effects can completely determine the structure of collisionless shocks mediated by energetic ions. Since the reduced form of the PUI-mediated plasma model is structurally identical to the classical cosmic ray two-fluid model, we note that the presence of viscosity, at least formally, eliminates the need for a gas sub-shock in the classical two-fluid model, including in that regime where three are possible. By considering parameters upstream of the HTS, we show that the thermal gas remains relatively cold and the shock is mediated by PUIs. We determine the structure of the weak interstellar shock observed by Voyager 1 . We consider the inclusion of the thermal heat flux and viscosity to address the most general form of an energetic particle-thermal plasma two-fluid model.

  15. Shock propagation in a heterogeneous medium

    International Nuclear Information System (INIS)

    Elbaz, D.

    2011-01-01

    In the frame of the inertial confinement fusion in direct drive, the use of foams as ablator allows the reduction of hydrodynamic instabilities created on the target by the direct laser irradiation. The foam is made up of carbon (CH) fibers impregnated of cryogenic deuterium-tritium (DT). In the past, studies have been carried out considering this foam to be a homogeneous medium. Yet, the foam presents heterogeneous features. We study the effects of this heterogeneity on the shock velocity when the laser irradiates the target. Thanks to experimental and numerical studies, we show that the shock propagates faster in the heterogeneous medium than in the homogeneous one with the same averaged density. This velocity gap depends on the presence rate of the CH fibers in the foam, the density ratio, the adiabatic coefficient and the foam geometry. We model the foam by different ways, more and more complex. The shock velocity modification is due to the baroclinicity which, during the interaction between the shock front and the interface, creates a vorticity deposition, responsible for the shock acceleration. Accordingly, an interface, which is plane and perpendicular to the front shock, maximizes the vorticity deposition and increases the velocity gaps between heterogeneous and homogeneous media. We found a correlation between the kinetic energy behind the shock front and the velocities relative difference. We compared our results with two analytical models. However, the system is not closed, so we can't for the moment develop a predictive model. (author) [fr

  16. Energetics of the terrestrial bow shock

    Science.gov (United States)

    Hamrin, Maria; Gunell, Herbert; Norqvist, Patrik

    2017-04-01

    The solar wind is the primary energy source for the magnetospheric energy budget. Energy can enter through the magnetopause both as kinetic energy (plasma entering via e.g. magnetic reconnection and impulsive penetration) and as electromagnetic energy (e.g. by the conversion of solar wind kinetic energy into electromagnetic energy in magnetopause generators). However, energy is extracted from the solar wind already at the bow shock, before it encounters the terrestrial magnetopause. At the bow shock the supersonic solar wind is slowed down and heated, and the region near the bow shock is known to host many complex processes, including the accelerating of particles and the generation of waves. The processes at and near the bow shock can be discussed in terms of energetics: In a generator (load) process kinetic energy is converted to (from) electromagnetic energy. Bow shock regions where the solar wind is decelerated correspond to generators, while regions where particles are energized (accelerated and heated) correspond to loads. Recently, it has been suggested that currents from the bow shock generator should flow across the magnetosheath and connect to the magnetospause current systems [Siebert and Siscoe, 2002; Lopez et al., 2011]. In this study we use data from the Magnetospheric MultiScale (MMS) mission to investigate the energetics of the bow shock and the current closure, and we compare with the MHD simulations of Lopez et al., 2011.

  17. Radiative shocks with electron thermal conduction

    International Nuclear Information System (INIS)

    Borkowski, Kazimierz.

    1988-01-01

    The authors studies the influence of electron thermal conduction on radiative shock structure for both one- and two-temperature plasmas. The dimensionless ratio of the conductive length to the cooling length determines whether or not conduction is important, and shock jump conditions with conduction are established for a collisionless shock front. He obtains approximate solutions with the assumptions that the ionization state of the gas is constant and the cooling rate is a function of temperature alone. In the absence of magnetic fields, these solutions indicate that conduction noticeably influences normal-abundance interstellar shocks with velocities 50-100 km s -1 and dramatically affects metal-dominated shocks over a wide range of shock velocities. Magnetic fields inhibit conduction, but the conductive energy flux and the corresponding decrease in the post-shock electron temperature may still be appreciable. He calculates detailed steady-state radiative shock models in gas composed entirely of oxygen, with the purpose of explaining observations of fast-moving knots in Cas A and other oxygen-rich supernova remnants (SNRs). The O III ion, whose forbidden emission usually dominates the observed spectra, is present over a wide range of shock velocities, from 100 to 170 kms -1 . All models with conduction have extensive warm photoionization zones, which provides better agreement with observed optical (O I) line strengths. However, the temperatures in these zones could be lowered by (Si II) 34.8 μm and (Ne II) 12.8 μm cooling if Si and Ne are present in appreciable abundance relative to O. Such low temperatures would be inconsistent with the observed (O I) emission in oxygen-rich SNRs

  18. Inhibitory action of chlorophyllin of autosome recessive lethals induced by irradiation

    International Nuclear Information System (INIS)

    Salceda, V.M.; Pimentel, P.A.E.; Cruces, M.P.

    2006-01-01

    The chlorophyllin is a sodium salt of the chlorophyll that has a strong protective action of the damage induced by different agents so much physical as chemical. In Drosophila there is reported this effect in somatic cells. In contrast, in germinal cells using tests with the sexual chromosomes has not been found such inhibitory action. For this reason, in this occasion we will refer to the effect of the lethality induced in autosome chromosomes, in particular to the chromosome II of this species. For such effect groups of males of the line Canton-S its were pre-treated for 24h with or without 69 mm of CCS and later on treaties with or without 40 Gy of gamma irradiation. The males were then subjected to the technical Cy L / Pm for the detection of recessive lethals. In the third generation the respective counts of the descendant of each one of them to determine the corresponding categories for each extracted chromosome were made. To be mendelian crosses it is expected for a normal chromosome a proportion 2:1 of individuals with genotype Cy L / +: +/+. The absence of individuals +/+ it is indicative of a lethal gene, until 10% of these individuals of each male's total descendant, it is considered that is carrying of a semi lethal gene. The sum of lethal and semi lethals constitutes the category detrimental. The obtained results indicated that the pre-treatment with CCS reduces in a significant way the frequency of induced lethals by 40 Gy of gamma rays. The fact that an effect inhibitor has not been observed in the test of recessive lethal bound to the sex obtained previously, it contrasts with the effect observed in the chromosome II, results of this study and with the one observed in the chromosome III in somatic cells. The above-mentioned shows a differential action of the CCS between sexual chromosomes and autosomal before the effect of the gamma radiation. At the moment we don't have an explanation to these evidences. To evaluate the action of the chlorophyllin

  19. EVALUATION OF SERUM LACTATE LEVELS AS A PROGNOSTIC INDICATOR IN VARIOUS TYPES OF SHOCK

    Directory of Open Access Journals (Sweden)

    Siddaraj Wali

    2017-08-01

    Full Text Available BACKGROUND Sepsis is a lethal disease that has a complex pathophysiology including a dysregulated inflammatory response, endothelial injury, microvascular thrombosis, vasoplegia and myocardial depression leading to multiorgan failure. Prompt recognition of sepsis, early initiation of antibiotics, source control, optimal fluid and vasopressor therapy are of utmost importance. Early diagnosis of sepsis is very critical for the timely and efficient use of treatment modalities, however, there are no reliable, specific biomarkers that can guide the diagnosis of sepsis. Cardiopulmonary failure, sepsis, trauma, oncologic pathology and so can lead to lactic acidosis. The aim of the study is to evaluate the serum lactic acid levels as a prognostic marker in various type of shock. MATERIALS AND METHODS It is a prospective clinical study with 50 patients studied for 1 year. To study the values of serum lactate levels in shock patients. Statistical analysis- Chi-square test 2. Student’s t-test (two tailed, independent. RESULTS Out of the 50 patients included in the study, the incidence of shock was found to be high in the 21-30 years age group, 13 (26%. This study of ours revealed the most common focus of sepsis as respiratory tract (60%, followed by urinary tract (25%, skin and soft tissue (15%. Out of the 18 patients who died, it was noted that mortality rates were highest 10 (55.5% in patients with initial (0 hours high positive serum lactate levels (>4 mmol/L. Out of the 32 patients who recovered, majority 21 (65.6% had low positive serum lactate levels (0-2.5 mmol/L on admission (0 hours. Serum lactate level is significantly reduced in recovered patients. CONCLUSION Approximately, 30% to 45% of patients with septic shock and 60% to 90% of patients with cardiogenic shock die within 1 month of presentation. Lactate was chosen because it is used as a prognostic marker of global hypoxia. Serial lactate values followed over a period of time can be used to

  20. DSMC Computations for Regions of Shock/Shock and Shock/Boundary Layer Interaction

    Science.gov (United States)

    Moss, James N.

    2001-01-01

    This paper presents the results of a numerical study of hypersonic interacting flows at flow conditions that include those for which experiments have been conducted in the Calspan-University of Buffalo Research Center (CUBRC) Large Energy National Shock (LENS) tunnel and the ONERA R5Ch low-density wind tunnel. The computations are made with the direct simulation Monte Carlo (DSMC) method of Bird. The focus is on Mach 9.3 to 11.4 flows about flared axisymmetric configurations, both hollow cylinder flares and double cones. The results presented highlight the sensitivity of the calculations to grid resolution, provide results concerning the conditions for incipient separation, and provide information concerning the flow structure and surface results for the extent of separation, heating, pressure, and skin friction.

  1. Streptococcal necrotizing fasciitis with toxic shock syndrome and rapid fatal outcome

    Directory of Open Access Journals (Sweden)

    Kojić Miroslav

    2015-01-01

    Full Text Available Introduction. Streptococcal necrotizing fasciitis (NF is a serious soft tissue infection with rapid progression of inflammatory process among superficial or deep fascia, systemic host response to infection leading to toxic shock syndrome (TSS, and multiple organ failure. Lethality is high. Case Outline. A 46-year-old male without co-morbidities was admitted to the Emergency Department with redness, swelling and pain on his right lower leg. He became sick two day s ea rlier with m alaise, chills and shivering. On admission he was hypotensive, anuric, with erythematous rash on his face, neck and chest, with acute ren al failure and elevated creatine phosphokinase level. During the next several hours, the changes on his right lower leg rapidly spread to the whole leg, followed by skin destruction and subcutaneo us bleeding, indicating NF. Aggressive antimicrobial, supportive and symptom atic therapy was initiated immediately and on the same evening surgical intervention was performed. Despite these measures, a rapid development of severe TSS, with lethal outcome, occurred in less than 40 hours after the admission. Stre ptococcus pyogenes (group A β-hemolytic Streptococcus was isolated from the throat, skin and tissue obtained duri ng the surgery. Conclusion. Necrotizing fasciitis is a very serious disease with unpre dictable course. For that reason doctors must devote a great deal of a ttention to early, i.e. timely diagnosis of this disease, whose treatment with a multid isciplinary approach is very important.

  2. Temperature measurements of shock-compressed deuterium

    International Nuclear Information System (INIS)

    Holmes, N.C.; Ross, M.; Nellis, W.J.

    1994-11-01

    The authors measured the temperatures of single and double-shocked D 2 and H 2 up to 85 GPa (0.85 Mbar) and 5,200 K. While single shock temperatures, at pressures to 23 GPa, agree well with previous models, the double shock temperatures are as much as 40% lower than predicted. This is believed to be caused by molecular dissociation, and a new model of the hydrogen EOS at extreme conditions has been developed which correctly predicts their observations. These data and model have important implications for programs which use condensed-phase hydrogen in implosion systems

  3. Recent oil price shock and Tunisian economy

    International Nuclear Information System (INIS)

    Jbir, Rafik; Zouari-Ghorbel, Sonia

    2009-01-01

    The objective of this paper is to study the oil prices-macroeconomy relationship by the analysis of the role of subsidy policy. The vector autoregression (VAR) method was employed to analyze the data over the period 1993 Q1 - 2007 Q3. The results of the model using both linear and non-linear specifications indicate that there is no direct impact of oil price shock on the economic activity. The shock of oil prices affects economic activity indirectly. The most significant channel by which the effects of the shock are transmitted is the government's spending. (author)

  4. Delayed Failure in a Shock Loaded Alumina

    International Nuclear Information System (INIS)

    Cooper, G. A.; Millett, J. C. F.; Bourne, N. K.; Dandekar, D. P.

    2006-01-01

    Manganin stress gauges have been used to measure the lateral stress in a shock-loaded alumina. In combination with known longitudinal stresses, these have been used to determine the shear strength of this material, behind the shock front. The two-step nature of the lateral stress traces shows a slow moving front behind the main shock, behind which shear strength undergoes a significant decrease. Results also show that this front decreases markedly in velocity as the HEL is crossed, suggesting that limited plasticity occurs during inelastic deformation. Finally, comparison of measured shear strengths with other aluminas shows a high degree of agreement

  5. Turbulent energy generated by accelerations and shocks

    International Nuclear Information System (INIS)

    Mikaelian, K.O.

    1986-01-01

    The turbulent energy generated at the interface between two fluids undergoing a constant acceleration or a shock is calculated. Assuming linear density profiles in the mixed region we find E/sub turbulent//E/sub directed/ = 2.3A 2 % (constant acceleration) and 9.3A 2 % (shock), where A is the Atwood number. Diffusion models predict somewhat less turbulent energy and a density profile with a tail extending into the lower density fluid. Eddy sizes are approximately 27% (constant acceleration) and 17% (shock) of the mixing depth into the heavier fluid. 6 refs., 3 figs

  6. Fine Mapping and Transcriptome Analysis Reveal Candidate Genes Associated with Hybrid Lethality in Cabbage (Brassica Oleracea).

    Science.gov (United States)

    Xiao, Zhiliang; Hu, Yang; Zhang, Xiaoli; Xue, Yuqian; Fang, Zhiyuan; Yang, Limei; Zhang, Yangyong; Liu, Yumei; Li, Zhansheng; Liu, Xing; Liu, Zezhou; Lv, Honghao; Zhuang, Mu

    2017-06-05

    Hybrid lethality is a deleterious phenotype that is vital to species evolution. We previously reported hybrid lethality in cabbage ( Brassica oleracea ) and performed preliminary mapping of related genes. In the present study, the fine mapping of hybrid lethal genes revealed that BoHL1 was located on chromosome C1 between BoHLTO124 and BoHLTO130, with an interval of 101 kb. BoHL2 was confirmed to be between insertion-deletion (InDels) markers HL234 and HL235 on C4, with a marker interval of 70 kb. Twenty-eight and nine annotated genes were found within the two intervals of BoHL1 and BoHL2 , respectively. We also applied RNA-Seq to analyze hybrid lethality in cabbage. In the region of BoHL1 , seven differentially expressed genes (DEGs) and five resistance (R)-related genes (two in common, i.e., Bo1g153320 and Bo1g153380 ) were found, whereas in the region of BoHL2 , two DEGs and four R-related genes (two in common, i.e., Bo4g173780 and Bo4g173810 ) were found. Along with studies in which R genes were frequently involved in hybrid lethality in other plants, these interesting R-DEGs may be good candidates associated with hybrid lethality. We also used SNP/InDel analyses and quantitative real-time PCR to confirm the results. This work provides new insight into the mechanisms of hybrid lethality in cabbage.

  7. Underwater electrical wire explosion: Shock wave from melting being overtaken by shock wave from vaporization

    Science.gov (United States)

    Li, Liuxia; Qian, Dun; Zou, Xiaobing; Wang, Xinxin

    2018-05-01

    The shock waves generated by an underwater electrical wire explosion were investigated. A microsecond time-scale pulsed current source was used to trigger the electrical explosion of copper wires with a length of 5 cm and a diameter of 200 μm. The energy-storage capacitor was charged to a relatively low energy so that the energy deposited onto the wire was not large enough to fully vaporize the whole wire. Two shock waves were recorded with a piezoelectric gauge that was located at a position of 100 mm from the exploding wire. The first and weak shock wave was confirmed to be the contribution from wire melting, while the second and stronger shock wave was the contribution from wire vaporization. The phenomenon whereby the first shock wave generated by melting being overtaken by the shock wave due to vaporization was observed.

  8. Multiple spacecraft observations of interplanetary shocks Four spacecraft determination of shock normals

    Science.gov (United States)

    Russell, C. T.; Mellott, M. M.; Smith, E. J.; King, J. H.

    1983-01-01

    ISEE 1, 2, 3, IMP 8, and Prognoz 7 observations of interplanetary shocks in 1978 and 1979 provide five instances where a single shock is observed by four spacecraft. These observations are used to determine best-fit normals for these five shocks. In addition to providing well-documented shocks for future investigations these data allow the evaluation of the accuracy of several shock normal determination techniques. When the angle between upstream and downstream magnetic field is greater than 20 deg, magnetic coplanarity can be an accurate single spacecraft method. However, no technique based solely on the magnetic measurements at one or multiple sites was universally accurate. Thus, the use of overdetermined shock normal solutions, utilizing plasma measurements, separation vectors, and time delays together with magnetic constraints, is recommended whenever possible.

  9. Reliability assessment of competing risks with generalized mixed shock models

    International Nuclear Information System (INIS)

    Rafiee, Koosha; Feng, Qianmei; Coit, David W.

    2017-01-01

    This paper investigates reliability modeling for systems subject to dependent competing risks considering the impact from a new generalized mixed shock model. Two dependent competing risks are soft failure due to a degradation process, and hard failure due to random shocks. The shock process contains fatal shocks that can cause hard failure instantaneously, and nonfatal shocks that impact the system in three different ways: 1) damaging the unit by immediately increasing the degradation level, 2) speeding up the deterioration by accelerating the degradation rate, and 3) weakening the unit strength by reducing the hard failure threshold. While the first impact from nonfatal shocks comes from each individual shock, the other two impacts are realized when the condition for a new generalized mixed shock model is satisfied. Unlike most existing mixed shock models that consider a combination of two shock patterns, our new generalized mixed shock model includes three classic shock patterns. According to the proposed generalized mixed shock model, the degradation rate and the hard failure threshold can simultaneously shift multiple times, whenever the condition for one of these three shock patterns is satisfied. An example using micro-electro-mechanical systems devices illustrates the effectiveness of the proposed approach with sensitivity analysis. - Highlights: • A rich reliability model for systems subject to dependent failures is proposed. • The degradation rate and the hard failure threshold can shift simultaneously. • The shift is triggered by a new generalized mixed shock model. • The shift can occur multiple times under the generalized mixed shock model.

  10. Shock wave physics group (M-6)

    International Nuclear Information System (INIS)

    Morris, C.E.

    1981-01-01

    Experimental facilities and activities of the shock wave physics group at LASL are described. The facilities include a compressed gas gun, two-stage gas gun, high explosive facilities, and a pulsed megagauss field facility

  11. Integrated microelectromechanical gyroscope under shock loads

    Science.gov (United States)

    Nesterenko, T. G.; Koleda, A. N.; Barbin, E. S.

    2018-01-01

    The paper presents a new design of a shock-proof two-axis microelectromechanical gyroscope. Without stoppers, the shock load enables the interaction between the silicon sensor elements. Stoppers were installed in the gyroscope to prevent the contact interaction between electrodes and spring elements with fixed part of the sensor. The contact of stoppers occurs along the plane, thereby preventing the system from serious contact stresses. The shock resistance of the gyroscope is improved by the increase in its eigenfrequency at which the contact interaction does not occur. It is shown that the shock load directed along one axis does not virtually cause the movement of sensing elements along the crosswise axes. Maximum stresses observed in the proposed gyroscope at any loading direction do not exceed the value allowable for silicon.

  12. Tribology Aspect of Rubber Shock Absorbers Development

    Directory of Open Access Journals (Sweden)

    M. Banić

    2013-09-01

    Full Text Available Rubber is a very flexible material with many desirable properties Which enable its broad use in engineering practice. Rubber or rubber-metal springs are widely used as anti-vibration or anti-shock components in technical systems. Rubber-metal springs are usually realized as a bonded assembly, however especially in shock absorbers, it is possible to realize free contacts between rubber and metal parts. In previous research it authors was observed that friction between rubber and metal in such case have a significant influence on the damping characteristics of shock absorber. This paper analyzes the development process of rubber or rubber-metal shock absorbers realized free contacts between the constitutive parts, starting from the design, construction, testing and operation, with special emphasis on the development of rubber-metal springs for the buffing and draw gear of railway vehicles.

  13. Role of drifts in diffusive shock acceleration

    International Nuclear Information System (INIS)

    Decker, R.B.

    1988-01-01

    The role played by shock-associated drifts during the diffusive acceleration of charged particles at collisionless MHD shocks is evaluated. In the rest frame of the shock, the total energy gained by a particle is shown to result from two coupled acceleration mechanisms, the usual first-order Fermi mechanism and the drift mechanism. When averaged over a distribution of particles, the ratio of the drift-associated energy gain to the total energy is found to be independent of the total energy at a given theta1 (the angle between the shock normal and the unperturbed upstream magnetic field) in agreement with theoretical predictions. No evidence is found for drift-associated deceleration, suggesting that drifts always augment acceleration. 35 references

  14. Shock Thermodynamic Applied Research Facility (STAR)

    Data.gov (United States)

    Federal Laboratory Consortium — The STAR facility, within Sandia's Solid Dynamic Physics Department, is one of a few institutions in the world with a major shock-physics program. This is the only...

  15. Nonequilibrium recombination after a curved shock wave

    Science.gov (United States)

    Wen, Chihyung; Hornung, Hans

    2010-02-01

    The effect of nonequilibrium recombination after a curved two-dimensional shock wave in a hypervelocity dissociating flow of an inviscid Lighthill-Freeman gas is considered. An analytical solution is obtained with the effective shock values derived by Hornung (1976) [5] and the assumption that the flow is ‘quasi-frozen’ after a thin dissociating layer near the shock. The solution gives the expression of dissociation fraction as a function of temperature on a streamline. A rule of thumb can then be provided to check the validity of binary scaling for experimental conditions and a tool to determine the limiting streamline that delineates the validity zone of binary scaling. The effects on the nonequilibrium chemical reaction of the large difference in free stream temperature between free-piston shock tunnel and equivalent flight conditions are discussed. Numerical examples are presented and the results are compared with solutions obtained with two-dimensional Euler equations using the code of Candler (1988) [10].

  16. Critical point anomalies include expansion shock waves

    Energy Technology Data Exchange (ETDEWEB)

    Nannan, N. R., E-mail: ryan.nannan@uvs.edu [Mechanical Engineering Discipline, Anton de Kom University of Suriname, Leysweg 86, PO Box 9212, Paramaribo, Suriname and Process and Energy Department, Delft University of Technology, Leeghwaterstraat 44, 2628 CA Delft (Netherlands); Guardone, A., E-mail: alberto.guardone@polimi.it [Department of Aerospace Science and Technology, Politecnico di Milano, Via La Masa 34, 20156 Milano (Italy); Colonna, P., E-mail: p.colonna@tudelft.nl [Propulsion and Power, Delft University of Technology, Kluyverweg 1, 2629 HS Delft (Netherlands)

    2014-02-15

    From first-principle fluid dynamics, complemented by a rigorous state equation accounting for critical anomalies, we discovered that expansion shock waves may occur in the vicinity of the liquid-vapor critical point in the two-phase region. Due to universality of near-critical thermodynamics, the result is valid for any common pure fluid in which molecular interactions are only short-range, namely, for so-called 3-dimensional Ising-like systems, and under the assumption of thermodynamic equilibrium. In addition to rarefaction shock waves, diverse non-classical effects are admissible, including composite compressive shock-fan-shock waves, due to the change of sign of the fundamental derivative of gasdynamics.

  17. Shock Wave Science and Technology Reference Library

    CERN Document Server

    2007-01-01

    Shock waves in multiphase flows refers to a rich variety of phenomena of interest to physicists, chemists, and fluid dynamicists, as well as mechanical, biomedical and aeronautical engineers. This volume treats shock and expansion waves in (bullet) complex, bubbly liquids (L van Wijngaarden, Y Tomita, V Kedrinskii) and (bullet) cryogenic liquids (M Murakami) and examines the relationship of shock waves with (bullet) phase transitions (A Guha, CF Delale, G Schnerr, MEH van Dongen) (bullet) induced phase transitions (GEA Meier) as well as their interaction with (bullet) solid foams, textiles, porous and granular media (B Skews, DMJ Smeulders, MEH van Dongen, V Golub, O Mirova) All chapters are self-contained, so they can be read independently, although they are of course thematically interrelated. Taken together, they offer a timely reference on shock waves in multiphase flows, including new viewpoints and burgeoning developments. The book will appeal to beginners as well as professional scientists and engineer...

  18. Comments on ''Analysis of spherical imploding shocks''

    International Nuclear Information System (INIS)

    Lazarus, R.B.

    1980-01-01

    It is asserted that Fujimoto and Mishkin's article is incorrect in its claim for a pressure extremum at or behind the shock for all values of γ and in its claim for an analytical form for the similarity exponent

  19. Shock-induced modification of inorganic powders

    International Nuclear Information System (INIS)

    Graham, R.A.; Morosin, B.; Venturini, E.L.; Beauchamp, E.K.; Hammetter, W.F.

    1984-01-01

    The results of studies performed to quantify the characteristics of TiO2, ZrO2 and Si3N4 powders exposed to explosive loading and post-shock analysis are reported. The shocks were produced with plane wave generators and explosive pads impinging on steel disks, a copper recovery fixture, and then the samples. Peak pressures of 13 and 17 GPa were attained, along with 40 GPz at the center of the powder cavity. Data are provided on the changes occurring during the explosive densification and X-ray and paramagnetic studies of the products. Only fractured disks were obtained in the trials. The shock-treated materials were more free flowing than the original powders, which were fluffy. Post-shock annealing was a significant feature of the treated powders

  20. SPECIAL PURPOSE SHOCK TUBE for BLAST ASSESSMENT

    Data.gov (United States)

    Federal Laboratory Consortium — This device is a specially designed shock tube for testing fabric samples in a controlled environment. The device determines the appropriate types of sensors to be...

  1. Collisions on relativistic nuclei: shock waves

    International Nuclear Information System (INIS)

    Gudima, K.K.; Toneev, V.D.

    1976-01-01

    Experiments are analysed which indicate the possible generation of shock waves in collisions of two nuclei. Another interpretation of these data is proposed and the concerned new experiments are discussed

  2. Analysis of Z Pinch Shock Wave Experiments

    International Nuclear Information System (INIS)

    Asay, James; Budge, Kent G.; Chandler, Gordon; Fleming, Kevin; Hall, Clint; Holland, Kathleen; Konrad, Carl; Lawrence, Jeffery; Trott, Wayne; Trucano, Timothy

    1999-01-01

    In this paper, we report details of our computational study of two shock wave physics experiments performed on the Sandia Z machine in 1998. The novelty of these particular experiments is that they represent the first successful application of VISAR interferometry to diagnose shock waves generated in experimental payloads by the primary X-ray pulse of the machine. We use the Sandia shock-wave physics code ALEGRA to perform the simulations reported in this study. Our simulations are found to be in fair agreement with the time-resolved VISAR experimental data. However, there are also interesting and important discrepancies. We speculate as to future use of time-resolved shock wave data to diagnose details of the Z machine X-ray pulse in the future

  3. Shock Tube Measurements for Liquid Fuels Combustion

    National Research Council Canada - National Science Library

    Hanson, Ronald K

    2006-01-01

    ...) fundamental studies of fuel spray evaporation rates and ignition times of low-vapor pressure fuels such as JP-8, diesel fuel and normal alkane surrogates in a new aerosol shock tube using state...

  4. Condensed matter at high shock pressures

    Energy Technology Data Exchange (ETDEWEB)

    Nellis, W.J.; Holmes, N.C.; Mitchell, A.C.; Radousky, H.B.; Hamilton, D.

    1985-07-12

    Experimental techniques are described for shock waves in liquids: Hugoniot equation-of-state, shock temperature and emission spectroscopy, electrical conductivity, and Raman spectroscopy. Experimental data are reviewed and presented in terms of phenomena that occur at high densities and temperatures in shocked He, Ar, N/sub 2/, CO, SiO/sub 2/-aerogel, H/sub 2/O, and C/sub 6/H/sub 6/. The superconducting properties of Nb metal shocked to 100 GPa (1 Mbar) and recovered intact are discussed in terms of prospects for synthesizing novel, metastable materials. Ultrahigh pressure data for Cu is reviewed in the range 0.3 to 6TPa (3 to 60 Mbar). 56 refs., 9 figs., 1 tab.

  5. Shock wave science and technology reference library

    CERN Document Server

    2009-01-01

    This book, as a volume of the Shock Wave Science and Technology Reference Library, is primarily concerned with detonation waves or compression shock waves in reactive heterogeneous media, including mixtures of solid, liquid and gas phases. The topics involve a variety of energy release and control processes in such media - a contemporary research field that has found wide applications in propulsion and power, hazard prevention as well as military engineering. The six extensive chapters contained in this volume are: - Spray Detonation (SB Murray and PA Thibault) - Detonation of Gas-Particle Flow (F Zhang) - Slurry Detonation (DL Frost and F Zhang) - Detonation of Metalized Composite Explosives (MF Gogulya and MA Brazhnikov) - Shock-Induced Solid-Solid Reactions and Detonations (YA Gordopolov, SS Batsanov, and VS Trofimov) - Shock Ignition of Particles (SM Frolov and AV Fedorov) Each chapter is self-contained and can be read independently of the others, though, they are thematically interrelated. They offer a t...

  6. Comparative review of bow shocks and magnetopauses

    International Nuclear Information System (INIS)

    Lepping, R.P.

    1984-04-01

    Bow shock and magnetopauses formation is discussed. Plasma and magnetic field environments of all the planets from Mercury to Saturn were measured. It was found that all the planets have bow shocks and almost all have a magnetopause. Venus is the only planet with no measurable intrinsic magnetic field and the solar wind interacts directly with Venus ionosphere. The bow shock characteristics depend on the changing solar wind conditions. The shape of a magnetopause or any obstacle to flow depends on the three dimensional pressure profile that it presents to the solar wind. Jupiter is unusual because of the considerable amount of plasma which is contained in its magnetosphere. Magentopause boundaries in ecliptic plane projection are modelled by segments of ellipses, matched to straight lines for the magnetotool boundaries or parabolas. Specific properties of known planetary bow shocks and magnetopauses are reviewed

  7. Medical and biomedical applications of shock waves

    CERN Document Server

    Loske, Achim M

    2017-01-01

    This book provides current, comprehensive, and clear explanations of the physics behind medical and biomedical applications of shock waves. Extracorporeal shock wave lithotripsy is one of the greatest medical advances of our time, and its techniques and clinical devices are continuously evolving. Further research continues to improve the understanding of calculi fragmentation and tissue-damaging mechanisms. Shock waves are also used in orthopedics and traumatology. Possible applications in oncology, cardiology, dentistry, gene therapy, cell transfection, transformation of fungi and bacteria, as well as the inactivation of microorganisms are promising approaches for clinical treatment, industrial applications and research. Medical and Biomedical Applications of Shock Waves is useful as a guide for students, technicians and researchers working in universities and laboratories. Chemists, biologists, physicians and veterinarians, involved in research or clinical practice will find useful advice, but also engineer...

  8. Relative locations of the bow shocks of the terrestrial planets

    International Nuclear Information System (INIS)

    Russell, C.T.

    1977-01-01

    The observed bow shock encounters at Mercury, Venus and Mars are least square fit using the same technique so that their sizes and shapes can be intercompared. The shock front of Mercury most resembles the terrestrial shock in shape, and the shock stand off distance is consistent with the observed moment. The shapes of the Venus and Mars shock fronts more resemble each other than the earth's and the stand off distances are consistent with direct interaction of the solar wind with the ionosphere on the dayside. The Venus shock is closer to the planet than the Mars shock suggesting more absorption of the solar wind at Venus

  9. Orientation Dependence in Molecular Dynamics Simulations of Shocked Single Crystals

    International Nuclear Information System (INIS)

    Germann, Timothy C.; Holian, Brad Lee; Lomdahl, Peter S.; Ravelo, Ramon

    2000-01-01

    We use multimillion-atom molecular dynamics simulations to study shock wave propagation in fcc crystals. As shown recently, shock waves along the direction form intersecting stacking faults by slippage along {111} close-packed planes at sufficiently high shock strengths. We find even more interesting behavior of shocks propagating in other low-index directions: for the case, an elastic precursor separates the shock front from the slipped (plastic) region. Shock waves along the direction generate a leading solitary wave train, followed (at sufficiently high shock speeds) by an elastic precursor, and then a region of complex plastic deformation. (c) 2000 The American Physical Society

  10. THE EFFECTS OF AREA CONTRACTION ON SHOCK WAVE STRENGTH AND PEAK PRESSURE IN SHOCK TUBE

    Directory of Open Access Journals (Sweden)

    A. M. Mohsen

    2012-06-01

    Full Text Available This paper presents an experimental investigation into the effects of area contraction on shock wave strength and peak pressure in a shock tube. The shock tube is an important component of the short duration, high speed fluid flow test facility, available at the Universiti Tenaga Nasional (UNITEN, Malaysia. The area contraction was facilitated by positioning a bush adjacent to the primary diaphragm section, which separates the driver and driven sections. Experimental measurements were performed with and without the presence of the bush, at various diaphragm pressure ratios, which is the ratio of air pressure between the driver (high pressure and driven (low pressure sections. The instantaneous static pressure variations were measured at two locations close to the driven tube end wall, using high sensitivity pressure sensors, which allow the shock wave strength, shock wave speed and peak pressure to be analysed. The results reveal that the area contraction significantly reduces the shock wave strength, shock wave speed and peak pressure. At a diaphragm pressure ratio of 10, the shock wave strength decreases by 18%, the peak pressure decreases by 30% and the shock wave speed decreases by 8%.

  11. Lethal action of canavanine in Escherichia coli; Etude de l'action lethale de la canavanine sur Escherichia coli

    Energy Technology Data Exchange (ETDEWEB)

    Simonnet, Gerard Marc

    1972-01-04

    proteines. La canavanine stimule la synthese de l'ARN dans les souches de bacteries RC{sup str} arg{sup -}, carencees en arginine; mais elle inhibe l'incorporation de l'uracile, l'UMP et d'UDP dans les souches RC{sup rel} arg{sup -}. En presence de canavanine, la replication de l'ADN suit le meme type de cinetique que dans les bacteries carencees en acide amine indispensable. L'ADN des bacteries incubees en presence de canavanine presente des alterations qui resultent de coupures de la molecule d'ADN. Il s'ensuit la formation de fragments d'ADN qui ne sedimentent pas a 10 000 xg avec les membranes cellulaires, ni a 150 000 xg en gradient de sucrose alcalin. L'action lethale de la canavanine doit etre le resultat de cette alteration de l'ADN. (auteur)

  12. The bureaucratization of war: moral challenges exemplified by the covert lethal drone

    Directory of Open Access Journals (Sweden)

    Richard Adams

    2013-12-01

    Full Text Available This article interrogates the bureaucratization of war, incarnate in the covert lethal drone. Bureaucracies are criticized typically for their complexity, inefficiency, and inflexibility. This article is concerned with their moral indifference. It explores killing, which is so highly administered, so morally remote, and of such scale, that we acknowledge a covert lethal program. This is a bureaucratized program of assassination in contravention of critical human rights. In this article, this program is seen to compromise the advance of global justice. Moreover, the bureaucratization of lethal force is seen to dissolve democratic ideals from within. The bureaucracy isolates the citizens from lethal force applied in their name. People are killed, in the name of the State, but without conspicuous justification, or judicial review, and without informed public debate. This article gives an account of the risk associated with the bureaucratization of the State's lethal power. Exemplified by the covert drone, this is power with formidable reach. It is power as well, which requires great moral sensitivity. Considering the drone program, this article identifies challenges, which will become more prominent and pressing, as technology advances.

  13. Plasma microRNA profiles distinguish lethal injury in acetaminophen toxicity: A research study

    Institute of Scientific and Technical Information of China (English)

    Jeanine Ward; Shashi Bala; Jan Petrasek; Gyongyi Szabo

    2012-01-01

    AIM:To investigate plasma microRNA (miRNA) profiles indicative of hepatotoxicity in the setting of lethal acetaminophen (APAP) toxicity in mice.METHODS:Using plasma from APAP poisoned mice,either lethally (500 mg/kg) or sublethally (150 mg/kg) dosed,we screened commercially available murine microRNA libraries (SABiosciences,Qiagen Sciences,MD) to evaluate for unique miRNA profiles between these two dosing parameters.RESULTS:We distinguished numerous,unique plasma miRNAs both up- and downregulated in lethally compared to sublethally dosed mice.Of note,many of the greatest up- and downregulated miRNAs,namely 574-5p,466g,466f-3p,375,29c,and 148a,have been shown to be associated with asthma in prior studies.Interestingly,a relationship between APAP and asthma has been previously well described in the literature,with an as yet unknown mechanism of pathology.There was a statistically significant increase in alanine aminotransferase levels in the lethal compared to sublethal APAP dosing groups at the 12 h time point (P <0.001).There was 90% mortality in the lethally compared to sublethally dosed mice at the 48 h time point (P =0.011).CONCLUSION:We identified unique plasma miRNAs both up- and downregulated in APAP poisoning which are correlated to asthma development.

  14. Damage to E. coli cells induced by tritium decay: secondary lethality under nongrowth conditions

    International Nuclear Information System (INIS)

    Koukalova, B.; Kuhrova, V.

    1980-01-01

    Cells containing incorporated 3 H-thymidine are damaged by its decay. It was found with E.coli TAU-bar cells that a small part of the damage is lethal whereas most of it is reparable and only potentially lethal. If cells are subjected to nongrowth conditions, the potentially lethal damage changes to lethal damage. This process is called secondary lethality (SL). The extent of SL and some changes in DNA under three different modes of growth inhibition were determined. It was found that: (i) SL is maximal under conditions of amino acid starvation (-AA), the viable count decreasing by two orders of magnitude. (ii) SL is 4 times lower in the presence of chloramphenicol (-AA+CLP) and 6.5 times lower under +AA+CLP conditions. Changes in the sedimentation rate of DNA determined in alkaline sucrose gradient correlate with the differences in SL: under -AA conditions the sedimentation rate of DNA decreases whereas in the presence of CLP no decrease occurs. The results suggest that certain enzymatic processes take place under -AA conditions which lead to irreparable changes in DNA. (author)

  15. Tolerization with BLP down-regulates HMGB1 a critical mediator of sepsis-related lethality.

    LENUS (Irish Health Repository)

    Coffey, J Calvin

    2012-02-03

    Tolerization with bacterial lipoprotein (BLP) affords a significant survival benefit in sepsis. Given that high mobility group box protein-1 (HMGB1) is a recognized mediator of sepsis-related lethality, we determined if tolerization with BLP leads to alterations in HMGB1. In vitro, BLP tolerization led to a reduction in HMGB1 gene transcription. This was mirrored at the protein level, as HMGB1 protein expression and release were reduced significantly in BLP-tolerized human THP-1 monocytic cells. BLP tolerance in vivo led to a highly significant, long-term survival benefit following challenge with lethal dose BLP in C57BL\\/6 mice. This was associated with an attenuation of HMGB1 release into the circulation, as evidenced by negligible serum HMGB1 levels in BLP-tolerized mice. Moreover, HMGB1 levels in peritoneal macrophages from BLP-tolerized mice were reduced significantly. Hence, tolerization with BLP leads to a down-regulation of HMGB1 protein synthesis and release. The improved survival associated with BLP tolerance could thus be explained by a reduction in HMGB1, were the latter associated with lethality in BLP-related sepsis. In testing this hypothesis, it was noted that neutralization of HMGB1, using anti-HMGB1 antibodies, abrogated BLP-associated lethality almost completely. To conclude, tolerization with BLP leads to a down-regulation of HMGB1, thus offering a novel means of targeting the latter. HMGB1 is also a mediator of lethality in BLP-related sepsis.

  16. The organisational structure of protein networks: revisiting the centrality-lethality hypothesis.

    Science.gov (United States)

    Raman, Karthik; Damaraju, Nandita; Joshi, Govind Krishna

    2014-03-01

    Protein networks, describing physical interactions as well as functional associations between proteins, have been unravelled for many organisms in the recent past. Databases such as the STRING provide excellent resources for the analysis of such networks. In this contribution, we revisit the organisation of protein networks, particularly the centrality-lethality hypothesis, which hypothesises that nodes with higher centrality in a network are more likely to produce lethal phenotypes on removal, compared to nodes with lower centrality. We consider the protein networks of a diverse set of 20 organisms, with essentiality information available in the Database of Essential Genes and assess the relationship between centrality measures and lethality. For each of these organisms, we obtained networks of high-confidence interactions from the STRING database, and computed network parameters such as degree, betweenness centrality, closeness centrality and pairwise disconnectivity indices. We observe that the networks considered here are predominantly disassortative. Further, we observe that essential nodes in a network have a significantly higher average degree and betweenness centrality, compared to the network average. Most previous studies have evaluated the centrality-lethality hypothesis for Saccharomyces cerevisiae and Escherichia coli; we here observe that the centrality-lethality hypothesis hold goods for a large number of organisms, with certain limitations. Betweenness centrality may also be a useful measure to identify essential nodes, but measures like closeness centrality and pairwise disconnectivity are not significantly higher for essential nodes.

  17. The frequency of allelic lethals and complementation maps in natural populations of drosophila melanogaster from Mexico

    Directory of Open Access Journals (Sweden)

    Salceda Victor M.

    2004-01-01

    Full Text Available Departing from a previous study on the genetic loads affecting the second chromosome of Drosophila melanogaster in four natural populations, 171 lethal chromosomes were recovered and maintained as a balanced stocks in the condition Cy L / 1 (l=lethal; of those lethais 24 correspond to population A, 50 to populations B and C and 47 to population D. later on an intra-population allelism test for the four populations was performed for each one. A total of 3807 inter lethal crosses were done yielding a total of i 10 allelic combinations, from them the respective percentage of allelism for each population was calculated and they are as follow: 3.98 % for population A, 1.80 % for population B, 3.67 % for population C and 2.96 % for population D. the observed values for the frequency of allelism in these populations are not significantly different from those reported by other authors in similar studies in natural and/or experimental populations. Beside these values the frequency for singles, doubles, triplets and even quadruplets present in each population were determined, they shown the presence of various complementation maps due to the clustering of few different lethals: also a large complementation map formed by a large cluster involving the presence of 26 different lethals found in population D all of them combined constituting a single unit was found.

  18. Damage to E. coli cells induced by tritium decay: secondary lethality under nongrowth conditions

    Energy Technology Data Exchange (ETDEWEB)

    Koukalova, B; Kuhrova, V [Ceskoslovenska Akademie Ved, Brno. Biofysikalni Ustav

    1980-05-01

    Cells containing incorporated /sup 3/H-thymidine are damaged by its decay. It was found with E.coli TAU-bar cells that a small part of the damage is lethal whereas most of it is reparable and only potentially lethal. If cells are subjected to nongrowth conditions, the potentially lethal damage changes to lethal damage. This process is called secondary lethality (SL). The extent of SL and some changes in DNA under three different modes of growth inhibition were determined. It was found that: (i) SL is maximal under conditions of amino acid starvation (-AA), the viable count decreasing by two orders of magnitude. (ii) SL is 4 times lower in the presence of chloramphenicol (-AA+CLP) and 6.5 times lower under +AA+CLP conditions. Changes in the sedimentation rate of DNA determined in alkaline sucrose gradient correlate with the differences in SL: under -AA conditions the sedimentation rate of DNA decreases whereas in the presence of CLP no decrease occurs. The results suggest that certain enzymatic processes take place under -AA conditions which lead to irreparable changes in DNA.

  19. Waves and Instabilities in Collisionless Shocks

    Science.gov (United States)

    1984-04-01

    occur in the electron foreshock and are driven by suprathermal electrons escaping into the region upstream of the shock. Both the ion-acoustic and...ULF waves occur in the ion foreshock and are associated with ions streaming into the region upstream of 11 the shock. The region downstream of the...the discussion of these waves it is useful to distinguish two regions, called the electron foreshock and the ion foreshock . Because the particles

  20. The Dynamic Quasiperpendicular Shock: Cluster Discoveries

    Czech Academy of Sciences Publication Activity Database

    Krasnoselskikh, V.; Balikhin, M.; Walker, S. N.; Schwartz, S.; Sundkvist, D.; Lobzin, V.; Gedalin, M.; Bale, S. D.; Mozer, F.; Souček, Jan; Hobara, Y.; Comisel, H.

    2013-01-01

    Roč. 178, 2-4 (2013), s. 535-598 ISSN 0038-6308 Institutional support: RVO:68378289 Keywords : collisionless shocks * waves in plasmas * nonstationarity * shock scales * plasma heating and acceleration * wave-particle interactions Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 5.874, year: 2013 http://link.springer.com/article/10.1007%2Fs11214-013-9972-y